Human anti-il-33 neutralizing monoclonal antibody

ABSTRACT

An antibody has an antagonistic effect against IL-33. In particular an isolated human anti-IL-33 neutralizing monoclonal antibody has framework regions with amino acid sequences from a germline, including combinations and fragments of such sequences. The epitopes for a plurality of anti-IL-33 monoclonal antibodies were identified, human anti-IL-33 neutralizing monoclonal antibodies were obtained, and the complementarity-determining regions that achieve high binding ability to IL-33 was specified by introducing mutations in the complementarity-determining regions. The identified complementarity-determining regions were used to produce the foregoing human anti-IL-33 neutralizing monoclonal antibodies having framework regions.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Continuation Application of U.S. application Ser. No. 15/621,950, filed Jun. 13, 2017, which is a Divisional Application of U.S. application Ser. No. 15/037,998, filed May 19, 2016, which issued as U.S. Pat. No. 9,758,578 on Sep. 12, 2017, which is the U.S. National Stage Application under 35 U.S.C. § 371 of International Application No. PCT/JP2014/084695, filed Dec. 26, 2014, designating the U.S. and published as WO 2015/099175 A1 on Jul. 2, 2015, which claims the benefit of Japanese Patent Application Nos. JP 2013-270551, filed Dec. 26, 2013, and JP 2014-078223, filed Apr. 4, 2014. Any and all applications for which a foreign or a domestic priority is claimed is/are identified in the Application Data Sheet filed herewith and is/are hereby incorporated by reference in their entirety under 37 C.F.R. § 1.57.

REFERENCE TO ELECTRONIC SEQUENCE LISTING

The present application is being filed along with an Electronic Sequence Listing in electronic format. The Electronic Sequence Listing is provided as a file entitled SWA018001C1SEQLIST.txt which is 262,898 bytes in size, created and last modified on May 16, 2019. The information in the Electronic Sequence Listing is incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present invention relates to a human anti-IL-33 neutralizing monoclonal antibody and an antibody which competes therewith; and a cytokine expression inhibitor containing any of such antibodies; and a pharmaceutical composition containing any of such antibodies for treatment, prevention, or alleviation of diseases associated with IL-33.

BACKGROUND ART

Interleukin-33 (hereinafter, referred to as IL-33) is a cytokine of the interleukin-1 family, which is believed to be involved in inflammatory conditions. IL-33 is constitutively expressed in the nuclei of epithelial cells and vascular endothelial cells, is released during cell destruction following tissue injury caused by infections or physical or chemical stress, and then acts as alarmin. It is also believed that IL-33 expression and secretion are increased by stimulation with lipopolysaccharide or the like in some mechanisms. The extracellularly released IL-33 binds to IL-33 receptors expressed on cells, thereby being capable of activating intracellular signal transduction. IL-33 receptors are expressed on various immune cells and epithelial cells, where IL-33-induced intracellular signal transduction occurs.

IL-33 is believed to induce allergic inflammation (for example, asthma, atopic dermatitis, pollinosis, and anaphylactic shock) by inducing production of Th2 cytokines (for example, IL-4, IL-5, IL-6, and IL-13) from Th2 cells, mast cells, eosinophils, basophils, natural killer T (NKT) cells, and Group 2 innate lymphocytes, among immune cells expressing IL-33 receptors (NPL 1: Tatsukuni Ohno et al., Allergy, 2012, Vol. 67, p. 1203). In mast cells and macrophages among the immune cells expressing IL-33 receptors, stimulation with IL-33 induces production of IL-1β, IL-6, and tumor necrosis factor α (TNF-α), which is suggested to be involved in the development of autoantibody-induced arthritis (model of rheumatoid arthritis) (NPL 2: Damo Xu et al., Journal of Immunology, 2010, Vol. 184, p. 2620). IL-33 antagonists are suggested to be effective against acute kidney injury (NPL 3: Ali Akcay et al., Journal of American Society Nephrology, 2011, Vol. 22, p. 2057). Increased IL-33 expression is observed in various human inflammatory diseases (for example, rheumatoid arthritis, asthma, systemic sclerosis, fibrosis such as hepatic fibrosis and pulmonary fibrosis, psoriasis, ulcerative colitis, Crohn's disease, multiple sclerosis, and ankylosing spondylitis), and IL-33 is believed to be involved in the development and maintenance of various diseases (NPL 4: Yasushi Matsuyama et al., Journal of Rheumatology, 2010, Vol. 37, p. 18; NPL 5: David Prefontaine et al., Journal of Allergy and Clinical Immunology, 2010, Vol. 125, p. 752; NPL 6: Koichi Yanaba et al., Clinical Rheumatology, 2011, Vol. 30, p. 825; NPL 7: A. L. Rankin et al., Journal of Immunology, 2010, Vol. 184, p. 1526; NPL 8: Tamar Mchedlidze et al., Immunity, 2013, Vol. 39, p. 357; NPL 9: Liang-An Hu et al., Asian Pacific Journal of Cancer Prevention, 2013, Vol. 14, p. 2563; NPL 10: Luca Pastorelli et al., Proceedings of the National Academy of Sciences of the United States of America, 2010, vol. 107, p. 8017).

Based on the knowledge on the association of IL-33 with various diseases, in particular inflammatory diseases, IL-33 agonists and antagonists have been developed (PTLs 1 to 4). Among the IL-33 agonists and antagonists, antibodies to IL-33 have been attracting attention, in view of their specificity and potency. Several antibodies which have been developed are directed to a murine antibody which fails to specify the epitope for the antibody (PTL 1); an antibody which recognizes a region including the caspase cleavage site of IL-33 residues 155 to 198 of SEQ ID NO:226 in the Sequence Listing) as epitope, based on the findings of the specific caspase cleavage site of IL-33 and the findings that the uncleaved form of IL-33 is the active form (PTL2); and several goat polyclonal antibodies which are commercially available. An article dated Jan. 10, 2014 on the website of AnaptysBio, Inc. reports their successful preparation of ANB020, the candidate for development of anti-IL-33 therapeutic antibody, using their proprietary somatic hypermutation technology (SHM-XEL) platform (NPL 11: Hamza Suria, ‘AnaptysBio announces development of novel anti-IL-33 therapeutic antibody’, [on line], 2014, [retrieved on 11 Jan. 2014], Retrieved from Internet:<URL: http://www.anaptysbio.com/anti-i1-33/>). Murphy et al. disclose that they prepared 20 types of human anti-IL-33 monoclonal antibodies using Veloclmmune mouse, that is, mouse transgenic for variable regions of a human antibody gene (PTL 5), but fail to disclose the epitope for the antibodies. In addition, the amino acid sequences of the framework regions of the 20 types of human anti-IL-33 monoclonal antibodies are different from human germline sequences in two or more amino acid residues. Due to such a difference, administration of these antibodies to human causes immune reaction to them to induce human anti-human immunoglobulin antibody (HAHA), which undesirably reduces the effects of the antibodies and induces inflammation or other side effects.

CITATION LIST Patent Literature

-   PTL 1: WO 2005/079844 -   PTL 2: WO 2008/132709 -   PTL 3: WO 2011/031600 -   PTL 4: WO 2008/144610 -   PTL 5: WO 2014/164959

Non Patent Literature

-   NPL 1: Tatsukuni Ohno et al., Allergy, 2012, Vol. 67, p. 120 -   NPL 2: Damo Xu et al., Journal of Immunology, 2010, Vol. 184, p.     2620 -   NPL 3: Ali Akcay et al., Journal of American Society Nephrology,     2011, Vol. 22, p. 2057 -   NPL 4: Yasushi Matsuyama et al., Journal of Rheumatology, 2010, Vol.     37, p. 18 -   NPL 5: David Prefontaine et al., Journal of Allergy and Clinical     Immunology, 2010, Vol. 125, p. 752 -   NPL 6: Koichi Yanaba et al., Clinical Rheumatology, 2011, Vol.     30, p. 825 -   NPL 7: A. L. Rankin et al., Journal of Immunology, 2010, Vol.     184, p. 1526 -   NPL 8: Tamar Mchedlidze et al., Immunity, 2013, Vol. 39, p. 357 -   NPL 9: Liang-An Hu et al., Asian Pacific Journal of Cancer     Prevention, 2013, Vol. 14, p. 2563 -   NPL 10: Luca Pastorelli et al., Proceedings of the National Academy     of Sciences of the United States of America, 2010, vol. 107, p. 8017 -   NPL 11: Hamza Suria, ‘AnaptysBio announces development of novel     anti-IL-33 therapeutic antibody’, [on line], 2014, [retrieved on 11     Jan. 2014], Retrieved from Internet: <URL:     http://www.anaptysbio.com/anti-i1-33/>

SUMMARY OF INVENTION Technical Problem

The association of IL-33 with some diseases has been clarified and development of an anti-IL-33 neutralizing monoclonal antibody having antagonistic effect against IL-33 has been required in recent years. The action of the anti-IL-33 neutralizing monoclonal antibody is closely related to the region of an epitope to which the antibody is to bind. Since IL-33 is extracellularly released during cell destruction, IL-33 is likely to be cleaved by lysosomal proteolytic enzymes, which may produce so-called mature IL-33 and many fragments derived from the mature IL-33 and having the activity of IL-33. If the fragments include an epitope consisting of a continuous amino acid sequence, a monoclonal antibody that is capable of binding to the epitope consisting of a continuous amino acid sequence of IL-33 is more advantageous than a monoclonal antibody that is capable of binding to an epitope consisting of a discontinuous amino acid sequence, because the former is capable of binding firmly to the continuous amino acid sequence of one of the fragments and inhibits the binding between the fragment and IL-33 receptors. However, it has remained difficult to identify such an epitope consisting of a continuous amino acid sequence for production of an anti-IL-33 monoclonal antibody having a desired antagonistic effect.

The anti-IL-33 neutralizing monoclonal antibody that is capable of binding to an epitope consisting of a continuous amino acid sequence of IL-33 preferably exhibits low antigenicity when it is administered to a human or the like. A human antibody preferably exhibits low antigenicity when it is administered to a human and has framework regions comprising amino acid sequences framework regions from a human germline or amino acid sequences consisting of a combination thereof. However, when the SHM-XEL platform or the like is applied to a human antibody contained in a human antibody gene library, amino acid sequence mutation occurs not only in the complementarity-determining regions but also in the framework regions. Furthermore, if a transgenic mouse induced with a gene of a human antibody is immunized with a human IL-33 protein to prepare a human anti-IL-33 neutralizing monoclonal antibody, mutation cannot be avoided in the amino acid sequences of the framework regions of the anti-IL-33 neutralizing monoclonal antibody. Accordingly, it has remained difficult to prepare an isolated anti-IL-33 human monoclonal antibody that includes framework regions comprising amino acid sequences of framework regions from a human germline or amino acid sequences consisting of the combination thereof.

Solution to Problem

The inventors, who have made extensive studies to solve the problems, found that an antibody that is capable of firmly binding to the epitope traditionally believed as preferred epitope, i.e. epitope present in a sequence spanning positions 155 to 198 of IL-33, has little antagonistic effect and that an epitope consisting of a continuous amino acid sequence present in a sequence spanning positions 101 to 154 or 199 to 270 of IL-33, in particular positions 111 to 130, 131 to 150, 231 to 250, or 251 to 270, is significant in view of the antagonistic effect of an antibody that is capable of binding to the epitope, and arrived at the present invention.

The inventors have also isolated a human anti-IL-33 neutralizing monoclonal antibody from a human antibody library, and have introduced mutations only in its complementarity-determining regions to identify the complementarity-determining regions that achieve excellent binding ability and physical properties. As a result, the inventors have successfully obtained a human antibody that has framework regions consisting of amino acid sequences without any mutation as compared to the amino acid sequences of the framework regions of the germline and is capable of binding to human IL-33 to neutralize its functions. The present invention involves the following aspects:

[1]. A monoclonal antibody that is capable of binding to an epitope consisting of a continuous amino acid sequence included in positions 101 to 154 or 199 to 270 of SEQ ID NO:226 in the Sequence Listing.

[2]. The antibody according to Aspect 1, wherein the epitope consisting of a continuous amino acid sequence included in positions 101 to 154 or 199 to 270 of SEQ ID NO:226 in the Sequence Listing consists of a continuous amino acid sequence included in positions 111 to 130, 131 to 150, 231 to 250, or 251 to 270 of SEQ ID NO:226 in the Sequence Listing.

[3]. The antibody according to Aspect 1 or 2, wherein the epitope consisting of a continuous amino acid sequence included in positions 101 to 154 or 199 to 270 of SEQ ID NO:226 in the Sequence Listing consists of an amino acid sequence including an amino acid selected from P118, I119, T120, Y122, L123, R124, S125, L126, S127, Y129, N130, D131, Q132, S133, T135, A137, L138, E139, S142, Y143, E144, I145, Y146, E148, D149, L150, D244, N245, H246, K266, L267, S268, and E269.

[4]. The antibody according to any one of Aspects 1 to 3, wherein the epitope consisting of a continuous amino acid sequence included in positions 101 to 154 or 199 to 270 of SEQ ID NO:226 in the Sequence Listing consists of a continuous amino acid of positions 111 to 130, 131 to 150, 231 to 250, or 251 to 270 of SEQ ID NO:226 in the Sequence Listing.

[5]. The antibody according to any one of Aspects 1 to 4, wherein the epitope consisting of a continuous amino acid sequence included in the sequence spanning positions 101 to 154 or 199 to 270 of SEQ ID NO:226 in the Sequence Listing consists of a continuous amino acid sequence of positions 138 to 147 or 139 to 147 of SEQ ID NO:226 in the Sequence Listing.

[6]. The antibody according to any one of Aspects 1 to 5, wherein the monoclonal antibody that is capable of binding to the epitope consisting of a continuous amino acid sequence included in positions 101 to 154 or 199 to 270 of SEQ ID NO:226 in the Sequence Listing is an IL-33 antagonist.

[7]. The antibody according to any one of Aspects 1 to 6, wherein the monoclonal antibody that is capable of binding to the epitope consisting of a continuous amino acid sequence included in positions 101 to 154 or 199 to 270 of SEQ ID NO:226 in the Sequence Listing inhibits binding between IL-33 receptors and IL-33.

[8]. A pharmaceutical composition for treatment, prevention, or alleviation of a disease associated with IL-33, comprising the antibody according to any one of Aspects 1 to 7.

[9]. A cytokine expression inhibitor comprising the antibody according to any one of Aspects 1 to 7.

[10]. The inhibitor according to Aspect 9, wherein the inhibitor inhibits expression of TNF-α, IFN-γ, IL-1β, IL-4, IL-5, IL-6, or IL-13.

[11]. The inhibitor according to Aspect 9 or 10, wherein the inhibitor inhibits expression of IFN-γ, IL-5, IL-6, or IL-13.

[12]. An epitope selected from the group consisting of:

1) the epitope according to any one of Aspects 1 to 5; 2) an epitope consisting of an amino acid sequence, wherein one or several amino acid are substituted, deleted, or added to the continuous amino acid sequence of the epitope of item 1; and 3) an epitope consisting of an amino acid sequence with at least 90% sequence identity to the continuous amino acid sequence of the epitope.

[13]. An antibody generated or screened using the epitope according to Aspect 12.

[14]. The antibody according to any one of Aspects 1 to 7, wherein the monoclonal antibody that is capable of binding to the epitope consisting of a continuous amino acid sequence included in positions 101 to 154 or 199 to 270 of SEQ ID NO:226 in the Sequence Listing is a chimeric, a humanized, or a human antibody.

[15]. The antibody according to Aspect 14, wherein the amino acid sequence of the framework regions is the amino acid sequences of framework regions from a human germline or a combination of the amino acid sequences thereof.

[16]. The antibody according to Aspect 15, wherein the amino acid sequence of the light-chain framework region 1 is residues 1 to 22 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 2 is residues 36 to 50 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 3 is residues 58 to 89 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 4 is residues 3 to 12 of SEQ ID NO:401 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 1 is residues 1 to 30 of SEQ ID NO:367 or residues 1 to 30 of SEQ ID NO:368 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 2 is residues 36 to 49 of SEQ ID NO:367 or residues 36 to 49 of SEQ ID NO:368 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 3 is residues 67 to 98 of SEQ ID NO:367 or residues 67 to 98 of SEQ ID NO:368 in the Sequence Listing; and the amino acid sequence of the heavy-chain framework region 4 is residues 5 to 15 of SEQ ID NO:407 in the Sequence Listing.

[17]. The antibody according to Aspect 15 or 16, wherein the amino acid sequence of the light-chain framework region 1 is residues 1 to 22 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 2 is residues 36 to 50 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 3 is residues 58 to 89 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 4 is residues 3 to 12 of SEQ ID NO:401 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 1 is residues 1 to 30 of SEQ ID NO:367 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 2 is residues 36 to 49 of SEQ ID NO:367 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 3 is residues 67 to 98 of SEQ ID NO:368 in the Sequence Listing; and the amino acid sequence of the heavy-chain framework region 4 is residues 5 to 15 of SEQ ID NO:407 in the Sequence Listing.

[18]. An isolated human anti-IL-33 neutralizing, wherein a combination of the amino acid sequences of the light-chain complementarity-determining region 1 (LCDR1), the light-chain complementarity-determining region 2 (LCDR2), the light-chain complementarity-determining region 3 (LCDR3), the heavy-chain complementarity-determining region 1 (HCDR1), the heavy-chain complementarity-determining region 2 (HCDR2), and the heavy-chain complementarity-determining region 3 (HCDR3) is selected from the combinations represented by C1 to C30 in Table 1:

TABLE 1 The following SEQ ID Nos. show the SEQ ID Nos. in the Sequence Listing LCDR1 LCDR2 LCDR3 HCDR1 HCDR2 HCDR3 C1 SEQ ID No. 1 SEQ ID No. 11 SEQ ID No. 22 SEQ ID No. 43 SEQ ID No. 51 SEQ ID No. 65 C2 SEQ ID No. 1 SEQ ID No. 11 SEQ ID No. 23 SEQ ID No. 43 SEQ ID No. 52 SEQ ID No. 65 C3 SEQ ID No. 2 SEQ ID No. 11 SEQ ID No. 23 SEQ ID No. 44 SEQ ID No. 52 SEQ ID No. 65 C4 SEQ ID No. 2 SEQ ID No. 11 SEQ ID No. 23 SEQ ID No. 44 SEQ ID No. 53 SEQ ID No. 65 C5 SEQ ID No. 2 SEQ ID No. 11 SEQ ID No. 23 SEQ ID No. 43 SEQ ID No. 54 SEQ ID No. 65 C6 SEQ ID No. 2 SEQ ID No. 11 SEQ ID No. 24 SEQ ID No. 45 SEQ ID No. 52 SEQ ID No. 65 C7 SEQ ID No. 2 SEQ ID No. 11 SEQ ID No. 23 SEQ ID No. 46 SEQ ID No. 52 SEQ ID No. 65 C8 SEQ ID No. 3 SEQ ID No. 12 SEQ ID No. 25 SEQ ID No. 47 SEQ ID No. 55 SEQ ID No. 66 C9 SEQ ID No. 4 SEQ ID No. 12 SEQ ID No. 26 SEQ ID No. 47 SEQ ID No. 56 SEQ ID No. 67 C10 SEQ ID No. 4 SEQ ID No. 13 SEQ ID No. 27 SEQ ID No. 47 SEQ ID No. 56 SEQ ID No. 67 C11 SEQ ID No. 5 SEQ ID No. 12 SEQ ID No. 28 SEQ ID No. 47 SEQ ID No. 56 SEQ ID No. 67 C12 SEQ ID No. 4 SEQ ID No. 12 SEQ ID No. 29 SEQ ID No. 47 SEQ ID No. 56 SEQ ID No. 67 C13 SEQ ID No. 6 SEQ ID No. 14 SEQ ID No. 30 SEQ ID No. 47 SEQ ID No. 56 SEQ ID No. 67 C14 SEQ ID No. 7 SEQ ID No. 14 SEQ ID No. 31 SEQ ID No. 47 SEQ ID No. 56 SEQ ID No. 67 C15 SEQ ID No. 4 SEQ ID No. 15 SEQ ID No. 32 SEQ ID No. 47 SEQ ID No. 56 SEQ ID No. 67 C16 SEQ ID No. 6 SEQ ID No. 16 SEQ ID No. 33 SEQ ID No. 48 SEQ ID No. 57 SEQ ID No. 68 C17 SEQ ID No. 4 SEQ ID No. 17 SEQ ID No. 34 SEQ ID No. 49 SEQ ID No. 58 SEQ ID No. 69 C18 SEQ ID No. 6 SEQ ID No. 18 SEQ ID No. 35 SEQ ID No. 47 SEQ ID No. 59 SEQ ID No. 70 C19 SEQ ID No. 6 SEQ ID No. 19 SEQ ID No. 36 SEQ ID No. 47 SEQ ID No. 56 SEQ ID No. 71 C20 SEQ ID No. 6 SEQ ID No. 20 SEQ ID No. 26 SEQ ID No. 47 SEQ ID No. 56 SEQ ID No. 66 C21 SEQ ID No. 6 SEQ ID No. 18 SEQ ID No. 37 SEQ ID No. 47 SEQ ID No. 60 SEQ ID No. 72 C22 SEQ ID No. 6 SEQ ID No. 20 SEQ ID No. 38 SEQ ID No. 47 SEQ ID No. 56 SEQ ID No. 73 C23 SEQ ID No. 8 SEQ ID No. 20 SEQ ID No. 27 SEQ ID No. 49 SEQ ID No. 56 SEQ ID No. 68 C24 SEQ ID No. 9 SEQ ID No. 20 SEQ ID No. 39 SEQ ID No. 47 SEQ ID No. 60 SEQ ID No. 73 C25 SEQ ID No. 4 SEQ ID No. 21 SEQ ID No. 34 SEQ ID No. 47 SEQ ID No. 61 SEQ ID No. 74 C26 SEQ ID No. 10 SEQ ID No. 19 SEQ ID No. 40 SEQ ID No. 47 SEQ ID No. 62 SEQ ID No. 75 C27 SEQ ID No. 4 SEQ ID No. 18 SEQ ID No. 41 SEQ ID No. 50 SEQ ID No. 56 SEQ ID No. 76 C28 SEQ ID No. 6 SEQ ID No. 20 SEQ ID No. 42 SEQ ID No. 47 SEQ ID No. 63 SEQ ID No. 77 C29 SEQ ID No. 2 SEQ ID No. 11 SEQ ID No. 23 SEQ ID No. 43 SEQ ID No. 64 SEQ ID No. 65 C30 SEQ ID No. 6 SEQ ID No. 20 SEQ ID No. 40 SEQ ID No. 47 SEQ ID No. 64 SEQ ID No. 78

[19]. The human anti-IL-33 neutralizing monoclonal antibody according to Aspect 18, wherein the combination of the amino acid sequences of the light-chain complementarity-determining region 1 (LCDR1), the light-chain complementarity-determining region 2 (LCDR2), the light-chain complementarity-determining region 3 (LCDR3), the heavy-chain complementarity-determining region 1 (HCDR1), the heavy-chain complementarity-determining region 2 (HCDR2), and the heavy-chain complementarity-determining region 3 (HCDR3) is selected from the combinations represented by C1 to C28 in Table 1.

[20]. The human anti-IL-33 neutralizing monoclonal antibody according to Aspect 18 or 19, wherein the combination of the amino acid sequences of the light-chain complementarity-determining region 1 (LCDR1), the light-chain complementarity-determining region 2 (LCDR2), the light-chain complementarity-determining region 3 (LCDR3), the heavy-chain complementarity-determining region 1 (HCDR1), the heavy-chain complementarity-determining region 2 (HCDR2), and the heavy-chain complementarity-determining region 3 (HCDR3) is selected from the combinations represented by C1, C8, C15, C17, and C18 in Table 1.

[21]. The human anti-IL-33 neutralizing monoclonal antibody according to any one of Aspects 18 to 20, wherein the amino acid sequence of the framework region of the antibody is the amino acid sequences of framework regions from a human germline or a combination of the amino acid sequences thereof.

[22]. The human anti-IL-33 neutralizing monoclonal antibody according to any one of Aspects 18 to 21, wherein the amino acid sequence of the light-chain framework region 1 is residues 1 to 22 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 2 is residues 36 to 50 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 3 is residues 58 to 89 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 4 is residues 3 to 12 of SEQ ID NO:401 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 1 is residues 1 to 30 of SEQ ID NO:367 or residues 1 to 30 of SEQ ID NO:368 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 2 is residues 36 to 49 of SEQ ID NO:367 or residues 36 to 49 of SEQ ID NO:368 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 3 is residues 67 to 98 of SEQ ID NO:367 or residues 67 to 98 of SEQ ID NO:368 in the Sequence Listing; and the amino acid sequence of the heavy-chain framework region 4 is residues 5 to 15 of SEQ ID NO:407 in the Sequence Listing.

[23]. The human anti-IL-33 neutralizing monoclonal antibody according to any one of Aspects 18 to 22, wherein the combination of respective amino acid sequences of light-chain and heavy-chain variable regions is selected from the combinations represented by V1 to V30 in Table 2:

TABLE 2 The following SEQ ID Nos. show the SEQ ID Nos. in the Sequence Listing Light Chain Heavy Chain Combination Variable Region Variable Region V1 SEQ ID No. 79 SEQ ID No. 105 V2 SEQ ID No. 80 SEQ ID No. 106 V3 SEQ ID No. 81 SEQ ID No. 107 V4 SEQ ID No. 81 SEQ ID No. 108 V5 SEQ ID No. 81 SEQ ID No. 109 V6 SEQ ID No. 82 SEQ ID No. 110 V7 SEQ ID No. 81 SEQ ID No. 111 V8 SEQ ID No. 83 SEQ ID No. 112 V9 SEQ ID No. 84 SEQ ID No. 113 V10 SEQ ID No. 85 SEQ ID No. 113 V11 SEQ ID No. 86 SEQ ID No. 113 V12 SEQ ID No. 87 SEQ ID No. 113 V13 SEQ ID No. 88 SEQ ID No. 113 V14 SEQ ID No. 89 SEQ ID No. 113 V15 SEQ ID No. 90 SEQ ID No. 113 V16 SEQ ID No. 91 SEQ ID No. 114 V17 SEQ ID No. 92 SEQ ID No. 115 V18 SEQ ID No. 93 SEQ ID No. 116 V19 SEQ ID No. 94 SEQ ID No. 117 V20 SEQ ID No. 95 SEQ ID No. 118 V21 SEQ ID No. 96 SEQ ID No. 119 V22 SEQ ID No. 97 SEQ ID No. 120 V23 SEQ ID No. 98 SEQ ID No. 121 V24 SEQ ID No. 99 SEQ ID No. 122 V25 SEQ ID No. 100 SEQ ID No. 123 V26 SEQ ID No. 101 SEQ ID No. 124 V27 SEQ ID No. 102 SEQ ID No. 125 V28 SEQ ID No. 103 SEQ ID No. 126 V29 SEQ ID No. 81 SEQ ID No. 127 V30 SEQ ID No. 104 SEQ ID No. 128

[24]. The human anti-IL-33 neutralizing monoclonal antibody according to Aspect 23, wherein the combination of respective amino acid sequences of the light-chain and heavy-chain variable regions is selected from the combinations represented by V1 to V28 in Table 2.

[25]. The human anti-IL-33 neutralizing monoclonal antibody according to Aspect 23 or 24, wherein the combination of the respective amino acid sequences of the light-chain and heavy-chain variable regions is selected from the combinations represented by V1, V8, V15, V17, and V18 in Table 2.

[26]. The human anti-IL-33 neutralizing monoclonal antibody according to any one of Aspects 18 to 25, wherein the light chain is a λ chain.

[27]. The human anti-IL-33 neutralizing monoclonal antibody according to any one of Aspects 18 to 26, wherein the human anti-IL-33 neutralizing monoclonal antibody is IgG.

[28]. The human anti-IL-33 neutralizing monoclonal antibody according to any one of Aspects 18 to 27, wherein the antigen is human IL-33 and monkey IL-33.

[29]. A nucleic acid molecule encoding a protein portion of the human anti-IL-33 neutralizing monoclonal antibody according to any one of Aspects 18 to 28.

[30]. The nucleic acid molecule according to Aspect 29, wherein a combination of nucleic acid sequences respectively encoding the amino acid sequences of the light-chain complementarity-determining region 1 (LCDR1), light-chain complementarity-determining region 2 (LCDR2), light-chain complementarity-determining region 3 (LCDR3), heavy-chain complementarity-determining region 1 (HCDR1), heavy-chain complementarity-determining region 2 (HCDR2) and heavy-chain complementarity-determining region 3 (HCDR3) is selected from the combinations represented by CN1 to CN30 in Table 3:

TABLE 3 The following SEQ ID Nos. show the SEQ ID Nos. in the Sequence Listing Combination LCDR1 LCDR2 LCDR3 HCDR1 HCDR2 HCDR3 CN1 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 129 No. 140 No. 156 No. 181 No. 191 No. 209 CN2 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 129 No. 140 No. 157 No. 181 No. 192 No. 209 CN3 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 130 No. 140 No. 157 No. 182 No. 192 No. 209 CN4 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 130 No. 140 No. 157 No. 182 No. 193 No. 209 CN5 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 130 No. 140 No. 157 No. 181 No. 194 No. 209 CN6 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 130 No. 140 No. 158 No. 183 No. 192 No. 209 CN7 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 130 No. 140 No. 157 No. 184 No. 192 No. 209 CN8 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 131 No. 141 No. 159 No. 185 No. 195 No. 210 CN9 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 132 No. 141 No. 160 No. 185 No. 196 No. 211 CN10 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 132 No. 142 No. 161 No. 185 No. 196 No. 211 CN11 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 133 No. 143 No. 162 No. 185 No. 196 No. 211 CN12 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 132 No. 141 No. 163 No. 185 No. 196 No. 211 CN13 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 134 No. 144 No. 164 No. 185 No. 196 No. 211 CN14 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 135 No. 144 No. 165 No. 185 No. 196 No. 211 CN15 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 132 No. 145 No. 166 No. 185 No. 196 No. 211 CN16 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 134 No. 146 No. 167 No. 186 No. 197 No. 212 CN17 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 132 No. 147 No. 168 No. 187 No. 198 No. 213 CN18 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 134 No. 148 No. 169 No. 185 No. 199 No. 214 CN19 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 134 No. 149 No. 170 No. 185 No. 200 No. 215 CN20 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 134 No. 150 No. 171 No. 185 No. 200 No. 216 CN21 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 134 No. 148 No. 172 No. 185 No. 201 No. 217 CN22 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 134 No. 150 No. 173 No. 185 No. 200 No. 218 CN23 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 136 No. 151 No. 174 No. 188 No. 202 No. 219 CN24 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 137 No. 151 No. 175 No. 189 No. 203 No. 220 CN25 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 138 No. 152 No. 176 No. 189 No. 204 No. 221 CN26 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 139 No. 153 No. 177 No. 189 No. 205 No. 222 CN27 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 138 No. 154 No. 178 No. 190 No. 206 No. 223 CN28 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 134 No. 155 No. 179 No. 185 No. 207 No. 224 CN29 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 130 No. 140 No. 157 No. 181 No. 208 No. 209 CN30 SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID SEQ ID No. 134 No. 155 No. 180 No. 185 No. 208 No. 225

[31]. A vector comprising the nucleic acid molecule according to Aspect 29 or 30.

[32]. A host cell comprising the vector according to Aspect 31.

[33]. A method of producing the human anti-IL-33 neutralizing monoclonal antibody according to any one of Aspects 18 to 28, comprising culturing the host cell according to Aspect 32.

[34]. A cytokine expression inhibitor comprising the human anti-IL-33 neutralizing monoclonal antibody according to any one of Aspects 18 to 28.

[35]. The inhibitor according to Aspect 34, wherein the inhibitor inhibits expression of TNF-α, IFN-γ, IL-1β, IL-4, IL-5, IL-6, or IL-13.

[36]. The inhibitor according to Aspect 34 or 35, wherein the inhibitor inhibits expression of IFN-γ, IL-5, IL-6, or IL-13.

[37]. A pharmaceutical composition comprising the human anti-IL-33 neutralizing monoclonal antibody according to any one of Aspects 18 to 28.

[38]. The pharmaceutical composition according to Aspect 37 for treatment, prevention, or alleviation of a disease associated with IL-33.

[39]. The pharmaceutical composition according to Aspect 38, wherein the disease associated with IL-33 is selected from the group consisting of asthma, atopic dermatitis, pollinosis, anaphylactic shock, sinusitis (including eosinophilic sinusitis), Crohn's disease, ulcerative colitis, arthritis, systemic lupus erythematosus, pemphigus, pemphigoid, scleroderma, ankylosing spondylitis, hepatic fibrosis (including primary biliary cirrhosis), pulmonary fibrosis, chronic obstructive pulmonary disease (COPD), acute kidney injury, vasculitis, and cancer.

[40]. An anti-IL-33 neutralizing monoclonal antibody which competes with the antibody according to Aspect 20 or 25 in binding to IL-33.

[41]. A method for treatment, prevention, or alleviation of symptom in a patient with a disease associated with IL-33, the method comprising administering the antibody according to any one of Aspects 1 to 7 and 18 to 28 to the patient.

[42]. The method according to Aspect 41, wherein the disease associated with IL-33 is selected from the group consisting of asthma, atopic dermatitis, pollinosis, anaphylactic shock, sinusitis (including eosinophilic sinusitis), Crohn's disease, ulcerative colitis, arthritis, systemic lupus erythematosus, pemphigus, pemphigoid, scleroderma, ankylosing spondylitis, hepatic fibrosis (including primary biliary cirrhosis), pulmonary fibrosis, chronic obstructive pulmonary disease (COPD), acute kidney injury, vasculitis, and cancer.

[43]. Use of the antibody according to any one of Aspects 1 to 7 and 18 to 28 for the manufacture of amedicament to treat, prevent, or alleviate a disease associated with IL-33.

[44]. The use according to Aspect 43, wherein the disease associated with IL-33 is selected from the group consisting of asthma, atopic dermatitis, pollinosis, anaphylactic shock, sinusitis (including eosinophilic sinusitis), Crohn's disease, ulcerative colitis, arthritis, systemic lupus erythematosus, pemphigus, pemphigoid, scleroderma, ankylosing spondylitis, hepatic fibrosis (including primary biliary cirrhosis), pulmonary fibrosis, chronic obstructive pulmonary disease (COPD), acute kidney injury, vasculitis, and cancer.

[45]. Use of the antibody according to any one of Aspects 1 to 7 and 18 to 28 for the treatment, prevention, or alleviation of a disease associated with IL-33.

[46]. The use according to Aspect 45, wherein the disease associated with IL-33 is selected from the group consisting of asthma, atopic dermatitis, pollinosis, anaphylactic shock, sinusitis (including eosinophilic sinusitis), Crohn's disease, ulcerative colitis, arthritis, systemic lupus erythematosus, pemphigus, pemphigoid, scleroderma, ankylosing spondylitis, hepatic fibrosis (including primary biliary cirrhosis), pulmonary fibrosis, chronic obstructive pulmonary disease (COPD), acute kidney injury, vasculitis, and cancer.

[47]. A method for treating, preventing, or alleviating a symptom in a patient in need of inhibition of cytokine expression, the method comprising administering the antibody according to any one of Aspects 1 to 7 and 18 to 28 to the patient.

[48]. The method according to Aspect 47, wherein the cytokine is TNF-α, IFN-γ, IL-1β, IL-4, IL-5, IL-6, or IL-13.

[49]. Use of the antibody according to any one of Aspects 1 to 7 and 18 to 28 for the manufacture of a cytokine expression inhibitor.

[50]. The use according to Aspect 49, wherein the cytokine is TNF-α, IFN-γ, IL-1β, IL-4, IL-5, IL-6, or IL-13.

Advantageous Effects of Invention

Since the monoclonal antibody of the present invention is capable of binding to an epitope consisting of a continuous amino acid sequence, the monoclonal antibody readily exhibits its neutralizing effect by binding to a continuous amino acid sequence, even in the case where IL-33 is cleaved into fragments

The monoclonal antibody of the present invention is less likely to induce human anti-human immunoglobulin antibody (HAHA) to its framework regions and/or complementarity-determining regions when it is administered to a human subject. Antibodies can exert a prolonged IL-33 neutralizing effect in vivo, unless they are inhibited by HAHA. In addition, antibodies are safely used, unless inflammation is caused by binding with HAHA. The monoclonal antibody of the present invention is capable of binding to human IL-33 to neutralize its functions, and thus is applicable to novel pharmaceuticals for diagnosis, prevention, treatment, or alleviation of diseases associated with IL-33.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows each domain and cleavage site of the IL-33 protein.

FIG. 2 shows a binding activity of each of antibodies to a human IL-33 protein (residues 112 to 270) and each partial peptide fragments thereof (PEP11 to PEP26).

FIG. 3 shows conformational model of a complex of mature human IL-33 (residues 117 to 270) (shown as “S117-T270” in FIG. 3) and human ST2 (hST2).

FIG. 4 shows a part of the conformational model in FIG. 3 illustrating human ST2 and a partial conformation of PEP12 epitope of human IL-33 (corresponding to positions 117 to 130 of SEQ ID NO:226 in the Sequence Listing and is represented by “5117-N130” in FIG. 4; hereinafter, other epitopes are represented in the same way).

FIG. 5 shows a part of the conformational model in FIG. 3 illustrating only PEP 14 epitope of human IL-33 and human ST2.

FIG. 6 shows a part of the conformational model in FIG. 3 illustrating only PEP24 epitope of human IL-33, d and human ST2.

FIG. 7 shows a part of the conformational model in FIG. 3 illustrating only PEP26 epitope of human IL-33, and human ST2.

FIG. 8 shows effects of a human anti-IL-33 neutralizing monoclonal antibody designated A25-3H04 on inflammation induced by intraperitoneal administration of human IL-33, based on inflammatory markers (spleen weight, serum IL-5 concentration, blood eosinophil count, blood basophil count, blood neutrophil count, serum IgA concentration, and serum IgE concentration).

FIG. 9 shows effects of human anti-IL-33 neutralizing monoclonal antibodies designated A10-1C04, A23-1A05, A25-2C02, and A26-1F02 on inflammation induced by intraperitoneal administration of human IL-33, based on inflammatory markers (spleen weight, blood eosinophil count, blood basophil count, blood neutrophil count, serum IgA concentration, and serum IgE concentration).

FIG. 10 shows variations in plasma concentration of each of the human anti-IL-33 neutralizing monoclonal antibodies (A23-1A05, A25-3H04, A26-1F02, A10-1C04, and A25-2C02) in mice.

FIG. 11 shows variations in serum concentration of each of the human anti-IL-33 neutralizing monoclonal antibodies (A10-1C04 and A23-1A05) in monkeys.

FIG. 12 shows the sequence and position of peptides PEP11 to PEP26.

DETAILED DESCRIPTION Definitions

The definitions of terms used herein are provided below for better understanding of the invention.

[Epitope]

As used herein, the term “epitope” refers to the part of an antigen recognized by an antibody. As used herein, the term “epitope” relates to a continuous amino acid sequence necessary for the recognition of the antibody.

[Binding]

As used herein, “binding” of a monoclonal antibody to an epitope refers to formation of a complex via binding between the antibody and the peptide which is an epitope. Examples of the binding between a monoclonal antibody and the epitope includes, but are not limited to, ionic, hydrogen, hydrophobic, and van der Waals bonds. Binding ability of a monoclonal antibody to an epitope can be analyzed, for example, by using peptide array scanning or KinExA technology described in the specification.

[Antibody]

The term “antibody” herein is used in the broadest sense, and includes monoclonal antibodies and polyclonal antibodies which exhibit desired binding specificity. The antibody of the present invention may be an antibody from any animal, and may be for example, a mouse antibody, a human antibody, a rat antibody, a rabbit antibody, a goat antibody, or a camel antibody.

[Monoclonal Antibody]

Among the antibodies of the present invention, “monoclonal antibody” refers to a population of antibodies produced from a single clone (i.e. the population includes substantially single molecular species) with respect to a designed amino acid sequence. Monoclonal antibodies include chimeric antibodies, humanized antibodies, human antibodies, multispecific antibodies, and artificial antibody, and functionally modified forms thereof, and conjugated antibodies containing any of such antibodies, and fragments of such antibodies. The monoclonal antibody of the present invention can be produced by any known method including, for example, hybridoma, phage display, and genetic engineering techniques.

[Chimeric Antibody]

The term “chimeric antibody” refers to an antibody containing light chains and/or heavy chains that are composed of variable regions of a non-human animal and constant regions of human.

[Humanized Antibody]

The term “humanized antibody” refers to an antibody which is composed of variable regions consisting of complementarity-determining regions of a non-human antibody and framework regions of a human antibody; and constant regions of a human antibody.

[Human Antibody]

The term “human antibody” refers to an antibody, wherein both light and heavy chains are derived from human. Human antibody includes the following isotypes with different heavy-chain constant regions: IgG (including IgG1, IgG2, IgG3, and IgG4) having γ heavy chains; IgM having μ heavy chains; IgA having α heavy chains (including IgA1 and IgA2); IgD having δ heavy chains; and IgE having ε heavy chains. In principle, each human antibody molecule has either κ or λ light chains.

[Multispecific Antibody]

The term “multispecific antibody” refers to an asymmetric antibody that has two or more independent antigen recognition sites and has specificity for two or more different antigens. Examples of the multispecific antibody include bispecific antibodies with specificity for two antigens, and trispecific antibodies with specificity for three antigens. One or more of the antigens recognized by the multispecific antibody of the present invention are an IL-33 molecule.

[Artificial Antibody]

“Artificial antibody” refers to, for example, protein scaffolds, which do not have a structure of an antibody, but have a function like an antibody. Examples of the applicable protein scaffolds include Kunitz domains of human serine protease inhibitors; extracellular domains of human fibronectin; ankyrin; and lipocalin. A protein scaffold that is capable of binding to the epitope of the present invention can be produced by modifying the sequence of the target-biding site on the scaffold (Clifford Mintz et. al., BioProcess International, 2013, Vol. 11(2), pp. 40-48).

[Functionally Modified Antibody]

As used herein, the term “functionally modified antibody” refers to an antibody which is regulated for its functions or properties, except for the antigen-binding function, such as cytotoxic function, complement activation function, and half-life in blood by mainly modifying amino acids or sugar chains in Fc regions of an antibody.

[Conjugated Antibody]

As used herein, the term “conjugated antibody” refers to an antibody which is conjugated with a non-antibody functional molecule, such as non-peptidic polymers, e.g., poly(ethylene glycol) (PEG); radioactive materials; toxins; low-molecular-weight compounds; cytokines; albumin; and enzymes through any chemical or genetic engineering process.

[Fragment]

As used herein, the term “antibody fragment” refers to a protein which comprises a part of an antibody and can bind to an antigen. Examples of the antibody fragment include Fab fragments, Fv fragments, F(ab′)₂ fragments, Fab′ fragments, and scFv fragments.

These antibody fragments may be conjugated with non-antibody functional molecules, such as non-peptidic polymers, e.g., poly(ethylene glycol) (PEG); radioactive materials; toxins; low-molecular-weight compounds; cytokines; albumin; and enzymes through any chemical or genetic engineering process.

[IL-33]

IL-33 is a cytokine of the IL-1 family. Human IL-33 consists of 270 amino acids as shown in SEQ ID NO:226 in the Sequence Listing. IL-33 comprises an N-terminal chromatin-binding domain, a C-terminal IL-1-like cytokine domain having 12 β-strands and having a molecular weight of 18 kDa, cathepsin G cleavage sites located at positions 95 and 109, an elastase cleavage site located at position 99, and a caspase cleavage site located at position 178 (FIG. 1). It is believed that, during cell necrosis, IL-33 is cleaved by enzymes, such as elastase, cathepsin G and proteinase 3, which are derived from loysosome etc., into various fragments including mature IL-33, such as IL-33 (residues 95 to 270) (“IL-33 (residues 95 to 270)” represents the IL-33 fragment represented by the amino acid sequence at positions 95 to 270 from N-terminus of SEQ ID NO:226 in the Sequence Listing; other fragments are represented in the same way), IL-33 (residues 99 to 270), IL-33 (resides 109 to 270), and IL-33 (residues 112 to 270)), and functions as a cytokine. In the case of apoptotic cell death, IL-33 is cleaved at position 178, by caspase activated during the apoptosis, into inactivated forms of IL-33, such as IL-33 (residues 179 to 270).

Once IL-33 is extracellularly released as a cytokine, it binds to IL-33 receptors and functions as an inducer of intracellular signal transduction in the cells expressing the IL-33 receptor. The IL-33-induced signal transduction occurs through pathways including, but not limited to, NF-κB and MAPKKs pathways, and eventually induces production of various cytokines, chemokines, and inflammatory mediators. Examples of the IL-33-induced cytokines include TNF-α, IL-1β, IFN-γ, IL-3, IL-4, IL-5, IL-6, and IL-13. In particular, production of IFN-γ, IL-5, IL-6, and IL-13 is induced. Examples of the IL-33-induced chemokines include CXCL2, CCL2, CCL3, CCL6, CCL17, and CCL24. Examples of the IL-33-induced inflammatory mediators include PGD2 and LTB4. The IL-33-induced cytokines, chemokines, and inflammatory mediators are involved in migration, cytokine production, and degranulation of immune cells, and cause inflammation. In the present invention, IL-33 may be either full-length IL-33 or any active fragment of IL-33, and may also be any derivative or variant thereof, as long as they are capable of binding to an IL-33 receptor described below and attain its effect. IL-33 may be either human IL-33 or IL-33 derived from any other organism. Among IL-33, human IL-33 represented by the amino acid sequence of SEQ ID NO:226 in the Sequence Listing is preferred.

The IL-33 receptor to which IL-33 binds is a heterodimeric complex composed of ST2 and IL-1RAcP (IL-1 receptor accessory protein). The IL-33 receptor contains the binding site that specifically recognizes IL-33 in the extracellular domain of ST2. The IL-33 receptor is expressed in cells including, but not limited to, various immune cells (such as Th2 cells, mast cells, eosinophils, basophils, macrophages, dendritic cells, NK cells, NKT cells, Group 2 innate lymphocytes (natural helper cells), nuocytes, and Ih2 (innate helper type 2) cells) and epithelial cells.

[Diseases Associated with IL-33]

As used herein, the term “disease associated with IL-33” refers to diseases caused by excessive extracellular release of IL-33. The diseases associated with IL-33 can be prevented, treated, or alleviated with an agent capable of inhibiting the functions of IL-33. The diseases associated with IL-33 include, for example, asthma, atopic dermatitis, pollinosis, anaphylactic shock, sinusitis (including eosinophilic sinusitis), Crohn's disease, ulcerative colitis, arthritis, systemic lupus erythematosus, pemphigus, pemphigoid, scleroderma, ankylosing spondylitis, hepatic fibrosis (including primary biliary cirrhosis), pulmonary fibrosis, chronic obstructive pulmonary disease (COPD), acute kidney injury, vasculitis, and cancer.

[Framework Region]

The term “framework region” refers to the part in variable regions of an immunoglobulin molecule other than complementarity-determining regions. Each light and heavy chain has four framework regions (framework regions 1, 2, 3, and 4). Herein, framework regions of immunoglobulin molecules are numbered in accordance with the Kabat numbering system (Kabat et al., 1987, Sequences of Proteins of Immunological Interest, US Department of Health and Human Services, NIH, USA).

[Germline]

The term “germline” refers to a group of germ cells such as spermatozoa and ovum, and refers to human germline, unless otherwise indicated. Immunoglobulin genes of germ cells contain no mutation, unlike those of B cells expressing antibodies. Accordingly, the term “amino acid sequence(s) of framework region(s) from germline” refers to amino acid sequence(s) without any mutation as compared to the amino acid sequence(s) of the framework region(s) of immunoglobulin. The term “a combination of amino acid sequences of framework regions from germlines” indicates that one or more of the four framework regions have an amino acid sequence of framework region from different germline. Gene that encode light-chain variable regions of human immune globulin is divided into Vκ segment and Jκ segment in κ chain; and Vλ segment and Jλ segment in λ chain. Framework regions 1 to 3 are present on the Vκ and Vλ segments, and framework region 4 is present on the Jκ and Jλ segments. The gene of the heavy-chain variable regions of human immunoglobulin is divided into VH segment, DH segment, and JH segment. Framework regions 1 to 3 are present on the VH segment, and framework region 4 is present on the JH segment. The germline amino acid sequences of each Vκ, Vλ, VH, Jκ, Jλ, and JH segment of human immunoglobulin are shown in Table 4.

TABLE 4 The following SEQ ID Nos. show the SEQ ID Nos. in the Sequence Listing Segment germline name SEQ ID No. Vκ Vκ1-5 SEQ ID No. 278 Vκ Vκ1-6 SEQ ID No. 279 Vκ Vκ1-8 SEQ ID No. 280 Vκ Vκ1-9 SEQ ID No. 281 Vκ Vκ1-12, Vκ1D-12 SEQ ID No. 282 Vκ Vκ1-16 SEQ ID No. 283 Vκ Vκ1-17 SEQ ID No. 284 Vκ Vκ1-27 SEQ ID No. 285 Vκ Vκ1-33, Vκ1D-33 SEQ ID No. 286 Vκ Vκ1-39, Vκ1D-39 SEQ ID No. 287 Vκ Vκ1D-8 SEQ ID No. 288 Vκ Vκ1D-13 SEQ ID No. 289 Vκ Vκ1D-16 SEQ ID No. 290 Vκ Vκ1D-17 SEQ ID No. 291 Vκ Vκ1D-43 SEQ ID No. 292 Vκ Vκ1-NL1 SEQ ID No. 293 Vκ Vκ2-24 SEQ ID No. 294 Vκ Vκ2-28, Vκ2D-28 SEQ ID No. 295 Vκ Vκ2-30 SEQ ID No. 296 Vκ Vκ2-40, Vκ2D-40 SEQ ID No. 297 Vκ Vκ2D-26 SEQ ID No. 298 Vκ Vκ2D-29 SEQ ID No. 299 Vκ Vκ2D-30 SEQ ID No. 300 Vκ Vκ3-11 SEQ ID No. 301 Vκ Vκ3-15, Vκ3D-15 SEQ ID No. 302 Vκ Vκ3-20 SEQ ID No. 303 Vκ Vκ3D-7 SEQ ID No. 304 Vκ Vκ3D-11 SEQ ID No. 305 Vκ Vκ3D-20 SEQ ID No. 306 Vκ Vκ3-NL1 SEQ ID No. 307 Vκ Vκ3-NL2 SEQ ID No. 308 Vκ Vκ3-NL3 SEQ ID No. 309 Vκ Vκ3-NL4 SEQ ID No. 310 Vκ Vκ3-NL5 SEQ ID No. 311 Vκ Vκ4-1 SEQ ID No. 312 Vκ Vκ5-2 SEQ ID No. 313 Vλ Vλ1-36 SEQ ID No. 314 Vλ Vλ1-40 SEQ ID No. 315 Vλ Vλ1-44 SEQ ID No. 316 Vλ Vλ1-47 SEQ ID No. 317 Vλ Vλ1-51 SEQ ID No. 318 Vλ Vλ2-8 SEQ ID No. 319 Vλ Vλ2-11 SEQ ID No. 320 Vλ Vλ2-14 SEQ ID No. 321 Vλ Vλ2-18 SEQ ID No. 322 Vλ Vλ2-23 SEQ ID No. 323 Vλ Vλ3-1 SEQ ID No. 324 Vλ Vλ3-9 SEQ ID No. 325 Vλ Vλ3-10 SEQ ID No. 326 Vλ Vλ3-12 SEQ ID No. 327 Vλ Vλ3-16 SEQ ID No. 328 Vλ Vλ3-19 SEQ ID No. 329 Vλ Vλ3-21 SEQ ID No. 330 Vλ Vλ3-22 SEQ ID No. 331 Vλ Vλ3-25 SEQ ID No. 332 Vλ Vλ3-27 SEQ ID No. 333 Vλ Vλ4-3 SEQ ID No. 334 Vλ Vλ4-60 SEQ ID No. 335 Vλ Vλ4-69 SEQ ID No. 336 Vλ Vλ5-37 SEQ ID No. 337 Vλ Vλ5-39 SEQ ID No. 338 Vλ Vλ5-45 SEQ ID No. 339 Vλ Vλ5-52 SEQ ID No. 340 Vλ Vλ6-57 SEQ ID No. 341 Vλ Vλ7-43 SEQ ID No. 342 Vλ Vλ7-46 SEQ ID No. 343 Vλ Vλ8-61 SEQ ID No. 344 Vλ Vλ9-49 SEQ ID No. 345 Vλ Vλ10-54 SEQ ID No. 346 VH VH1-2 SEQ ID No. 347 VH VH1-3 SEQ ID No. 348 VH VH1-8 SEQ ID No. 349 VH VH1-18 SEQ ID No. 350 VH VH1-24 SEQ ID No. 351 VH VH1-45 SEQ ID No. 352 VH VH1-46 SEQ ID No. 353 VH VH1-58 SEQ ID No. 354 VH VH1-f SEQ ID No. 355 VH VH1-69 SEQ ID No. 356 VH VH2-5 SEQ ID No. 357 VH VH2-26 SEQ ID No. 358 VH VH2-70 SEQ ID No. 359 VH VH3-7 SEQ ID No. 360 VH VH3-9 SEQ ID No. 361 VH VH3-11 SEQ ID No. 362 VH VH3-13 SEQ ID No. 363 VH VH3-15 SEQ ID No. 364 VH VH3-20 SEQ ID No. 365 VH VH3-21 SEQ ID No. 366 VH VH3-23 SEQ ID No. 367 VH VH3-30, VH3-30-3 SEQ ID No. 368 VH VH3-33 SEQ ID No. 369 VH VH3-43 SEQ ID No. 370 VH VH3-48 SEQ ID No. 371 VH VH3-49 SEQ ID No. 372 VH VH3-53 SEQ ID No. 373 VH VH3-64 SEQ ID No. 374 VH VH3-66 SEQ ID No. 375 VH VH3-72 SEQ ID No. 376 VH VH3-73 SEQ ID No. 377 VH VH3-74 SEQ ID No. 378 VH VH3-d SEQ ID No. 379 VH VH3-NL1 SEQ ID No. 380 VH VH4-4 SEQ ID No. 381 VH VH4-28 SEQ ID No. 382 VH VH4-30-2 SEQ ID No. 383 VH VH4-30-4 SEQ ID No. 384 VH VH4-31 SEQ ID No. 385 VH VH4-34 SEQ ID No. 386 VH VH4-39 SEQ ID No. 387 VH VH4-59 SEQ ID No. 388 VH VH4-b SEQ ID No. 389 VH VH4-61 SEQ ID No. 390 VH VH5-a SEQ ID No. 391 VH VH5-51 SEQ ID No. 392 VH VH6-1 SEQ ID No. 393 VH VH7-4-1 SEQ ID No. 394 Jκ Jκ1 SEQ ID No. 395 Jκ Jκ2 SEQ ID No. 396 Jκ Jκ3 SEQ ID No. 397 Jκ Jκ4 SEQ ID No. 398 Jκ Jκ5 SEQ ID No. 399 Jλ Jλ1 SEQ ID No. 400 Jλ Jλ2, Jλ3 SEQ ID No. 401 Jλ Jλ6 SEQ ID No. 402 Jλ Jλ7 SEQ ID No. 403 JH JH1 SEQ ID No. 404 JH JH2 SEQ ID No. 405 JH JH3 SEQ ID No. 406 JH JH4 SEQ ID No. 407 JH JH5 SEQ ID No. 408 JH JH6 SEQ ID No. 409

[Human Monoclonal Antibody]

The term “human monoclonal antibody” refers to a monoclonal antibody containing variable and constant regions of human germline immunoglobulin sequence. In the present invention, the human monoclonal antibody may be a recombinant generated by replacing its variable regions partially or entirely with variable regions of any other human monoclonal antibody. The recombinant may be generated by recombination at boundaries between the framework regions and the complementarity-determining regions, in order to avoid undesired influences on the binding ability of the antibody. The recombinant may also be generated by recombination of framework regions 1 to 4 respectively with framework regions 1 to 4 of any other human monoclonal antibody, in order to avoid undesired increase in immunogenicity. The human monoclonal antibody of the present invention may be a variant of a human monoclonal antibody. In order to reduce immunogenicity while maintaining or improving its binding ability with the antigen, the human monoclonal antibody preferably includes amino acid sequences of complementarity-determining region with mutation and amino acid sequences of germline framework region without mutation.

[Isolated]

The term “isolated” antibody refers to an antibody identified and separated and/or recovered from a component in its natural environment. Contaminant components in its natural environments are materials that would interfere with diagnostic or therapeutic uses of the antibody, and include enzymes, hormones, and other proteinaceous or non-proteinaceous solutes. In general, an isolated antibody may be obtained by at least one purification step, and an antibody purified by such at least one purification step is referred to as “isolated antibody.”

[Neutralization]

As used herein, the term “neutralization” refers to an action of binding to a target of interest and inhibiting one of its functions. Specifically, the term “anti-IL-33 neutralizing monoclonal antibody” refers to a monoclonal antibody which inhibits biological activity induced by the IL-33 polypeptide via binding with IL-33. The biological activity to be inhibited of IL-33 includes, but is not limited to, production of IL-33-induced cytokines such as IL-6. Indicators of the biological activity of IL-33 can be evaluated by one or more of the in vitro or in vivo analyses known in the art. The term “human anti-IL-33 neutralizing monoclonal antibody” refers to a human monoclonal antibody that is capable of binding to IL-33 to inhibit one of its functions.

[Antagonist]

As used herein, the term “antagonist” is a generic term for materials having a neutralizing effect on a target of interest. Specifically, “IL-33 antagonist” refers to a material capable of binding to IL-33 to inhibit one of its functions, for example anti-IL-33 neutralizing monoclonal antibodies.

[Complementarity-Determining Region]

The term “complementarity-determining regions” refers to the regions which form the antigen-binding site in variable regions of an immunoglobulin molecule. It is also referred to as “hypervariable regions” indicating the parts with particularly great variability in the amino acid sequences among different immunoglobulin molecules. Light and heavy chains respectively contain three complementarity-determining regions (complementarity-determining regions 1, 2, and 3). In the present invention, the complementarity-determining regions of immunoglobulin molecules are numbered in accordance with the Kabat numbering system (Kabat et al., 1987, Sequences of Proteins of Immunological Interest, US Department of Health and Human Services, NIH, USA).

[Competition]

As used herein, an antibody which “competes” with a monoclonal antibody indicates that the presence of the monoclonal antibody significantly decreases the binding of an antibody with IL-33, as measured by surface plasmon resonance (SPR) as described in the specification.

As used herein, the term “anti-IL-33 neutralizing monoclonal antibody which competes” encompasses chimeric antibodies, humanized antibodies, human antibodies, multispecific antibodies, and artificial antibody, and functionally modified forms thereof, conjugated antibodies containing any of such antibodies, and fragments of such antibodies.

The embodiments of the present invention are explained below. The following embodiments is illustrative, and should not be construed to limit the present invention.

The present invention relates to a monoclonal antibody that is capable of binding to an epitope of IL-33. Since the monoclonal antibody that is capable of binding to the epitope can neutralize the activity of human IL-33, the epitope preferably has an amino acid sequence of positions 101 to 154 or 199 to 270, more preferably 111 to 130 (PEP12), 131 to 150 (PEP14), 231 to 250 (PEP24), or 251 to 270 (PEP26), of SEQ ID NO:226 in the Sequence Listing. IL-33 is often cleaved during extracellular release. If an epitope is formed from amino acid residues being separate on on the primary sequence of IL-33 based on protein folding, cleavage of IL-33 affects the protein folding and deletes the separated amino acid residues of the epitope, which may result in significant decrease of the affinity of the antibody with the resulting fragments. For this reason, the epitope to which the anti-IL-33 monoclonal antibody binds is preferably a continuous amino acid sequence.

In order to attain the neutralizing effect of the monoclonal antibody that is capable of binding to an epitope, it is required, for example, to inhibit binding of IL-33 with IL-33 receptors. Thus, the epitope in the present invention is preferably present not only on the surface of the IL-33 protein but also in close proximity to the IL-33 receptors. The inventors have performed conformational modeling based on the crystallographic structure data in NPL 11, to identify the amino acids containing the atom of IL-33 located at the atomic distance of 5 Å or less from a component atom of the IL-33 receptor, when the two atoms are in the closest proximity (i.e. interfacial atom), as described below in the Examples. Examples of the amino acid containing the interfacial atom include P118 (“P118” represents the proline residue at position 118 of SEQ ID NO:226 in the Sequence Listing; hereinafter, amino acid residues are represented in the same way), 1119, T120, Y122, L123, R124, S125, L126, S127, Y129, and N130 of PEP12; D131, Q132, S133, T135, A137, L138, E139, S142, Y143, E144, 1145, Y146, E148, D149, and L150 of PEP14; D244, N245, and H246 of PEP24; and K266, L267, S268, and E269 of PEP26. A functional epitope to specifically bind to a monoclonal antibody that can neutralize IL-33 preferably includes the amino acid containing the interfacial atom. The neutralizing effect of a monoclonal antibody that is capable of specifically binding to a functional epitope is believed to depend on the number and the conformational position of the interfacial atoms contained in the functional epitope, but it is not intended to be bound by the theory.

A preferred embodiment of the present invention is directed to a monoclonal antibody wherein the epitope consisting of a continuous amino acid sequence included in positions 101 to 154 or 199 to 270 of SEQ ID NO:226 in the Sequence Listing consists of a continuous amino acid sequence of positions 111 to 130 (PEP12), 131 to 150 (PEP14), 231 to 250 (PEP24), or 251 to 270 (PEP26) of SEQ ID NO:226 in the Sequence Listing. A more preferred embodiment of the present invention is the monoclonal antibody wherein the epitope consists of a continuous amino acid sequence of positions 138 to 147 or 139 to 147 of SEQ ID NO:226 in the Sequence Listing.

The inventors have studied the minimal amino acid sequence required for the epitope, using two different monoclonal antibodies that bind to PEP14, and have determined the continuous amino acid sequences of positions 138 to 147 and 139 to 147 of SEQ ID NO:226 in the Sequence Listing as the minimal sequence for the epitope of IL-33. Accordingly, the present invention relates to an epitope consisting of a continuous amino acid sequence of positions 138 to 147 or 139 to 147 of SEQ ID NO:226 in the Sequence Listing.

The binding of a monoclonal antibody to the epitope of the present invention can be confirmed by a method generally practiced in the art, such as ELISA, immunoprecipitation, surface plasmon resonance (SPR), and KinExA technology. For example, if a monoclonal antibody is tested using the epitope peptides of the present invention in peptide array scanning based on the SPR process, as described in the Examples in the specification, the binding of the monoclonal antibody to the epitope can be determined based on significant increases in RU values. The analysis by KinExA technology described in the specification in the Examples can determine a dissociation constant (Kd). The dissociation constant against an epitope peptide is preferably low, and is preferably 10 μM or lower, 1 μM or lower, 100 nM or lower, 10 nM or lower, 1 nM or lower, 100 pM or lower, or 10 pM or lower.

Another embodiment of the present invention relates to a pharmaceutical composition comprising the monoclonal antibody of the present invention that is capable of binding to an epitope consisting of a continuous amino acid sequence included in positions 101 to 154 or 199 to 270 of SEQ ID NO:226 in the Sequence Listing. The invention also relates to a method for diagnosis, treatment, prevention, or alleviation of a disease associated with IL-33, the method comprising administering the monoclonal antibody of the invention, and to use of the monoclonal antibody of the invention for the manufacture of a amedicament to diagnosing, treating, preventing, or alleviating a disease associated with IL-33.

Non-limiting examples of the disease associated with IL-33 include asthma, atopic dermatitis, urticaria, pollinosis, anaphylactic shock, sinusitis (including eosinophilic sinusitis), allergic encephalomyelitis, hypereosinophilic syndrome, polymyalgia rheumatica, rheumatic heart diseases, multiple sclerosis, arthritis (for example, rheumatoid arthritis, juvenile arthritis, psoriatic arthritis, arthrosis deformans, and Reiter's syndrome), systemic lupus erythematosus (including discoid lupus), pemphigus, pemphigoid, psoriasis, ankylosing spondylitis, hepatitis (for example, autoimmune hepatitis and chronic active hepatitis), inflammatory bowel diseases (for example, ulcerative colitis, Crohn's disease, and gluten-sensitive enteropathy), Sjogren's syndrome, autoimmune hemolytic anemia, autoimmune inflammatory eye diseases, autoimmune neonatal thrombocytopenia, autoimmune neutropenia, autoimmune oophoritis and orchitis, autoimmune thrombocytopenia, autoimmune thyroiditis, multiple myositis, dermatomyositis, myasthenia gravis, adrenergic agonist resistance, alopecia areata (alopecia greata), antiphospholipid syndrome, adrenal autoimmune diseases (for example, autoimmune Addison's disease), celiac sprue-dermatitis, chronic fatigue and immune dysfunction syndrome (CFIDS), cold agglutinin disease, essential mixed cryoglobulinemia, fibromyalgia-fibromyositis, glomerulonephritis (for example, IgA nephropathy), Graves' disease, hyperthyroidism (that is, Hashimoto's thyroiditis), idiopathic thrombocytopenic purpura (ITP), mixed connective tissue disease, Type 1 or immune-mediated diabetes mellitus, pernicious anemia, polychondritis, polyglandular syndrome, stiff-man syndrome, vitiligo, sarcoidosis, polyendocrinopathy, other endocrinopathy, arteriosclerosis, hepatic fibrosis (for example, primary biliary cirrhosis), pulmonary fibrosis (for example, idiopathic pulmonary fibrosis), chronic obstructive pulmonary disease (COPD), scleroderma (including CREST syndrome and Raynaud's phenomenon), tubulointerstitial nephritis, dense deposit disease, acute kidney injury, myocarditis, cardiomyopathy, neuritis (for example, Guillain-Barre syndrome), polyarteritis nodosa, cardiotomy syndrome, chronic inflammatory demyelinating polyneuropathy, IgA neuropathy, lichen planus, Meniere's disease, post-myocardial infarction (post-MI) syndrome, uveitis, uveitis ophthalmia, vasculitis, primary agammaglobulinemia, cancer (for example, brain tumor, laryngeal cancer, lip and oral cancer, hypopharyngeal cancer, thyroid cancer, esophageal cancer, breast cancer, lung cancer, gastric cancer, adrenocortical carcinoma, cancer of the bile duct, gallbladder cancer, liver cancer, pancreatic cancer, bladder cancer, colon cancer, uterine cancer, ovarian cancer, prostate cancer, testicular cancer, chronic lymphocytic leukemia, chronic myelogenous leukemia, Ewing's tumor, Hodgkin's disease, non-Hodgkin lymphoma, melanoma, mesothelioma, and multiple myeloma), infections resistant to clearance by the immune system (for example, severe acute respiratory syndrome (SARS)), lethal cytokine storm associated with virulent influenza infection, and sepsis. The disease associated with IL-33 is preferably asthma, atopic dermatitis, pollinosis, anaphylactic shock, sinusitis (including eosinophilic sinusitis), Crohn's disease, ulcerative colitis, arthritis, systemic lupus erythematosus, pemphigus, pemphigoid, scleroderma, ankylosing spondylitis, hepatic fibrosis (including primary biliary cirrhosis), pulmonary fibrosis, chronic obstructive pulmonary disease (COPD), acute kidney injury, vasculitis, and cancer.

A further embodiment of the present invention relates to an expression inhibitor against a cytokine, chemokine, or an inflammatory mediator, comprising the monoclonal antibody that is capable of binding to an epitope consisting of a continuous amino acid sequence included in positions 101 to 154 or 199 to 270 of SEQ ID NO:226 in the Sequence Listing.

The cytokine to be inhibited by the expression inhibitor for cytokines, chemokines, or inflammatory mediators according to the present invention is one of the IL-33 induced cytokines, including TNF-α, IFN-γ, IL-1β, IL-3, IL-4, IL-5, IL-6, and IL-13. The chemokine to be inhibited with the inhibitor is one of IL-33-induced chemokines, including CXCL2, CCL2, CCL3, CCL6, CCL17, and CCL24. The inflammatory mediator to be inhibited with the inhibitor is one of IL-33-induced inflammatory mediators, including PGD2 and LTB4. A particularly preferred embodiment of the present invention is an expression inhibitor containing an anti-IL-33 monoclonal antibody to inhibit expression of IFN-γ, IL-5, IL-6, or IL-13. More preferably, the inhibitor is an IL-6 expression inhibitor.

In a further embodiment of the present invention, the invention relates to an epitope to which an anti-IL-33 monoclonal antibody binds. In the present invention, the epitope is directed to a sequence consisting of six to twenty amino acids necessary for recognition by the antibody. In another embodiment, the epitope may further contain amino acids in close proximity, either in the sequence or in the three-dimensional structure, to amino acids in the determined sequence, thereby a further epitope may be formed. However, the epitope preferably does not contain discontinuous amino acids.

The continuous amino acid sequence of the epitope of the present invention consists of at least five, preferably at least six, more preferably at least seven, more preferably at least eight, yet more preferably at least nine amino acids. The continuous amino acid sequence consists of at least 10, more preferably 15, yet more preferably at least 20 amino acids, so as to achieve more sufficient antigenicity. On the other hand, if the epitope contains an excessively long sequence, however, it may contain two or more sites recognized by an antibody, which may interfere with production or screening of antibodies having a desired neutralizing effect. For this reason, the sequence of the epitope is preferably 30 amino acids or less, more preferably 20 amino acids or less, yet more preferably 15 amino acids or less, in length, for ensuring exhibition of the desired neutralizing effect by the antibody that is capable of binding to the epitope of the present invention. The number of amino acid residues in the continuous amino acid sequence included in the epitope is selected from, for example, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, and 20.

The epitope may have one or several amino acid mutations, i.e. amino acid substitutions, deletions, or insertions, unless the mutations change the antigenicity. The number of introduced mutations is preferably five or less, more preferably three or less, most preferably one. The epitope may also be modified, for example, with sugar chains of the original protein, and terminal modification. In another embodiment, the epitope may consist of an amino acid sequence with sequence identity of at least 90%, more preferably at least 95%, more preferably at least 97%, yet more preferably at least 98%, most preferably 99%, to the continuous amino acid sequence specified in the present invention, unless the antigenicity is affected. The epitope peptide may be tagged with histidine or biotin, etc., when it is used as bait, and may be linked to a carrier protein such as KLH, when it is used as vaccine.

“Percent (%) sequence identity” related to a reference polypeptide sequence identified herein is defined as the percentage of amino acid residues that are included in a candidate sequence and are identical with the amino acid residues in a specific reference polypeptide sequence, after aligning the sequences and introducing gaps, if necessary, to achieve the maximum percent sequence identity, and not considering any conservative substitutions as part of the sequence identity. Alignment for the purpose of determining percent amino acid sequence identity can be achieved by using various methods within the skill in the art, for example, a publicly available computer software, such as BLAST, BLAST-2, ALIGN, or Megalign (DNASTAR, Inc.) software. Those skilled in the art can determine appropriate parameters for measuring alignment, including any algorithm necessary for achieving maximal alignment on the full-length sequences to be compared. For the purposes described herein, however, percent amino acid sequence identity values are determined by pairwise comparison using the sequence comparison computer program BLAST. In a circumstance where the program BLAST is used for comparison of amino acid sequences, the percent amino acid sequence identity of a given amino acid sequence A to a given amino acid sequence B is calculated as follows:

Fraction X/Y×100

where X is the number of amino acid residues scored as identical matches by the sequence alignment program BLAST in its alignment of the sequences A and B, and Y is the total number of amino acid residues in the sequence B. It will be appreciated that difference in length between the amino acid sequences A and B results in difference in the percent amino acid sequence identity of the sequence A to the sequence B and that of the sequence B to the sequence A. All the percent amino acid sequence identity values described herein are determined based on the BLAST computer program as just described above, unless otherwise indicated.

The epitope found in the present invention is directed to a functional epitope to which an anti-IL-33 neutralizing antibody binds specifically. Thus, a novel antibody having an antagonistic effect against IL-33 can be obtained efficiently by means of the functional epitope of the present invention. Specifically, a monoclonal antibody having the antagonistic effect can be obtained by screening monoclonal antibodies to full-length IL-33 or mature IL-33 to identify those which are capable of binding to the functional epitope of the invention. Accordingly, in a further embodiment, the present invention relates to a method of screening for an antibody having an antagonistic effect using the functional epitope of IL-33. More specifically, if a clone of antibody having an antagonistic effect against IL-33 is concentrated from a naive antibody library by phage display technique, library selection is first performed using a full-length or mature IL-33 protein as bait, the clones of antibodies that bind to one or more of various epitopes on the surface of IL-33 are enriched and then are subjected to the library selection using the functional epitope peptides found in the invention as bait. Such a method provides efficient screening of an antibody capable of specifically binding to the functional epitope and having an antagonistic effect against IL-33.

In the Examples, the inventors tested monoclonal antibodies that had been confirmed to bind to epitopes of 20 amino acid residues in length to analyze their antagonistic activity against IL-33 at different antibody concentrations, to determine epitopes suitable for production or screening of an antibody having the antagonistic effect. The results show that antibodies binding to an epitope selected from the group consisting of positions 111 to 130 (PEP12), 131 to 150 (PEP14), 231 to 250 (PEP24), and 251 to 271 (PEP26) of SEQ ID NO:226 in the Sequence Listing clearly exhibited concentration-dependent increase in their antagonistic effect. The results demonstrate that such epitopes are functional epitopes suitable for production or screening of an antibody having antagonistic effect. Accordingly, in one embodiment, the present invention relates to an epitope comprising a sequence consisting of at least six, preferably at least 10, more preferably at least 15, consecutive amino acids included in a region selected from the group consisting of positions 111 to 130, 131 to 150, 231 to 250, and 251 to 271 of SEQ ID NO:226 in the Sequence Listing. In another embodiment, the present invention relates to an epitope selected from the group consisting of positions 111 to 130, 131 to 150, 231 to 250, and 251 to 270 of SEQ ID NO:226 in the Sequence Listing.

The epitope can be produced by any peptide synthesizing technique ordinarily practiced in the art. A prepared and purified epitope can be used for immunization of animals or for production of antibodies to the epitope. Alternatively, a purified epitope can be applied to phage displaying technique for production or screening of a monoclonal antibody that is capable of binding to the epitope. The epitope can also be used as vaccine when it is used in combination with an adjuvant.

The present invention relates to a monoclonal antibody that is capable of binding to an epitope consisting of a continuous amino acid sequence included in a sequence spanning positions 101 to 154 or 199 to 270 of SEQ ID NO:226 in the Sequence Listing. Examples of the monoclonal antibody include chimeric antibodies, humanized antibodies, human antibodies, multispecific antibodies, and artificial antibody; and functionally modified forms thereof, conjugated antibody thereof, and fragments thereof. The monoclonal antibody of the present invention may be an antibody from any animal, for example, mouse antibody, human antibody, rat antibody, rabbit antibody, goat antibody, or camel antibody. The monoclonal antibody of the present invention can be produced by a variety of known processes including, for example, hybridoma, phage display, and genetic engineering techniques.

In the hybridoma technique, an animal, in particular rat or mouse, is immunized with an immunogen, and B cells are collected from its spleen or lymph node and are then fused with immortalized cells, e.g., myeloma cells, to form hybridoma cells. The hybridoma cells are screened to identify the hybridoma that produces an antibody having the desired binding ability, and the desired antibody can be produced with the screened hybridoma. A human antibody can be obtained from a transgenic mouse induced with a gene for the human antibody. The monoclonal antibody of interest is obtained from the hybridoma cells by, for example, culturing the hybridoma cells in accordance with an ordinary method and then collecting the culture supernatant; or administering the hybridoma cells to a mammal which is compatible with the hybridoma cells for proliferation, and then collecting the ascitic fluid. The former method is suitable for production of antibodies at high purity, and the latter method is suitable for large-scale production of antibodies. Monoclonal antibodies can be prepared by any known technique, for example, in accordance with the description in Current Protocols in Immunology, Wiley and Sons Inc., Chapter 2.

In the phage display technique, phages selected from any phage antibody library are screened using an immunogen of interest to select the phages that have desired binding ability to the immunogen. The sequence contained in the selected phages and corresponding to the antibody is then isolated or determined, and an expression vector including a nucleic acid molecule that encodes a monoclonal antibody is constructed based on the isolated sequence or determined sequence information. The expression vector is then transfected into a cell line and the cell line is cultured to produce the monoclonal antibody. A human antibody with desired binding ability can be produced with a human antibody library as the phage antibody library.

In genetic engineering techniques, a recombinant antibody can be prepared by introducing a mutation in a sequence corresponding to complementarity-determining regions (CDR) or any other sequence within the gene sequence which encodes the antibody, incorporating the resulting sequence into an expression vector, and then transforming the expresion vector into a host cell (see, for example, Borrebaeck C. A. K. and Larrick J. W. THERAPEUTIC MONOCLONAL ANTIBODIES, Published in the United Kingdom by MACMILLAN PUBLISHERS LTD, 1990).

In the present invention, chimeric antibodies, humanized antibodies, multispecific antibodies, and artificial antibody mimetics can also be used, for example, for the purpose of reducing xenoantigenicity to human or adding other function. Such antibodies can be produced by any known method.

A chimeric antibody can be produced by ligating a DNA which encodes variable regions of a non-human antibody to a DNA which encodes constant regions of a human antibody, incorporating the resulting DNA into an expression vector, which is then transformed into a host cell for expression of the antibody of interest (see EP 125023 and WO 92/19759). Chimeric antibodies useful for the present invention can be produced by such a known technique.

A humanized antibody can be produced by ligating a DNA which encodes complementarity-determining regions (CDR) of a non-human antibody to a DNA which encodes the remaining regions of a human antibody, and incorporating the resulting DNA into an expression vector, which is then transformed into a host cell for expression of the antibody of interest.

A multispecific antibody refers to an asymmetric antibody that has two or more independent antigen recognition sites and have specificity for two or more different antigens. A multispecific antibody such as bispecific antibody can be produced by any genetic engineering technique based on antigen-binding regions of two or more monoclonal antibodies. Such genetic engineering techniques have already been established in the art. For example, a desired bispecific antibody can be obtained by linking antigen-binding regions of two different monoclonal antibodies in tandem in accordance with the DVD-Ig method (Wu et al., Nature Biotechnology 25(11), 1290(2007)), or by modifying Fc region of an antibody to combine heavy chains of two different antibodies that are capable of binding to different antigens in accordance with the ART-Ig method (Kitazawa et al., Nature Medicine 18(10), 1570(2012)).

“Artificial antibody” refers to, for example, protein scaffolds, which do not have a structure of an antibody, but have a function like an antibody. Examples of the applicable protein scaffolds include Kunitz domains of human serine protease inhibitors; extracellular domains of human fibronectin; ankyrin; and lipocalin. A protein scaffold that is capable of binding to the epitope of the present invention can be produced by modifying the sequence of the target-biding site on the scaffold (PTL 4; Clifford Mintz et. al BioProcess International, 2013, Vol. 11(2), pp. 40-48).

The monoclonal antibody of the present invention may be modified in its amino acid sequence or sugar chain structure in Fc regions to regulate its functions or properties, except for the antigen-binding function, such as cytotoxic function, complement activation function, and half-life in blood (Strobl, Current Opinion in Biotechnology, 2009, vol. 20, p. 685). Such a functionally modified antibody can be prepared, for example, by a method described below. A monoclonal antibody produced in CHO host cells knocked out for the α1,6-fucosyltransferase (FUT8) gene has a decreased fucose content on the sugar chains, resulting in increased cytotoxic function, while an antibody produced in CHO host cells transfected with the FUT 8 gene has low cytotoxic function (WO 2005/035586, WO 2002/31140, and WO 00/61739). The complement activation function of the antibody can be regulated by modification of its Fc region via change in amino acid residues (U.S. Pat. Nos. 6,737,056, 7,297,775, and 7,317,091). The half-life in blood of the antibody can be prolonged with an Fc region variant having increased binding ability to FcRn, one of Fc receptors (Shuhei Hashiguchi et al., SEIKAGAKU (The Journal of Biochemistry), 2010, Vol. 82(8), p. 710). Such functionally-modified antibodies can be produced by genetic engineering techniques.

The monoclonal antibody used in the present invention may be a conjugated antibody produced by binding an antibody to any of various molecules, such as non-peptidic polymers, e.g., poly(ethylene glycol) (PEG); radioactive materials; and toxins. Such a conjugated antibody can be produced through chemical modification of the obtained antibody. Methods for chemical modification have already been established in the art. Such conjugated antibodies are also encompassed in the monoclonal antibody of the present invention (D. J. King., Applications and Engineering of Monoclonal antibodies., 1998 T. J. International Ltd, Monoclonal Antibody-Based Therapy of Cancer., 1998 Marcel Dekker Inc; Chari et al., Cancer Res., 1992 Vol. 152:127; Liu et al., Proc Natl Acad Sci USA., 1996 Vol 93:8681).

According to the present invention, in addition to the full-length antibodies described above, the antibody also encompasses fragments of monoclonal antibodies and any modified forms thereof, as long as they have binding ability to an epitope of interest and exerts antagonistic activity. Examples of the antibody fragment include Fab fragments, Fv fragments, F(ab′)₂ fragments, Fab′ fragments, and single-chain Fv (scFv) fragments, which contain the Fv regions of the H and L chains connected via a suitable linker. These antibody fragments may be bound to non-antibody functional molecules, such as non-peptidic polymers, e.g., poly(ethylene glycol) (PEG); radioactive materials; toxins; low-molecular-weight compounds; cytokines; albumin; and enzymes.

The production system for preparing monoclonal antibodies may be any of in vitro and in vivo production systems. The in vitro production system includes the production system using eukaryotic cells, e.g., animal cells, plant cells, or fungal cells; and the production system using prokaryotic cells, e.g., bacterial cells such as Escherichia coli and Bacillus subtilis. Applicable cells include animal cells, in particular mammalian cells, e.g., generally used cells, such as CHO, COS, myeloma, BHK, HeLa, and Vero cells; insect cells; and plant cells. In vivo production system includes production systems in animals or plants. Examples of the production system in animals include those in mammals and insects. Examples of applicable mammals include goats, porcines, ovines, mice, and bovines (Vicki Glaser, SPECTRUM Biotechnology Applications, 1993). Examples of applicable insects include silkworms. Examples of applicable plants include tobacco.

If the monoclonal antibody is produced in an in vitro or in vivo production system as described above, the DNA encoding the heavy chain (H chain) and the DNA encoding the light chain (L chain) may be incorporated into separate expression vectors to co-transform the host, or may be incorporated together into a single expression vector to transform the host (see WO 94/11523).

The monoclonal antibody thus produced can be purified to homogeneity. The monoclonal antibodies can be separated and purified by any method ordinarily used for separation and purification of proteins. For example, the monoclonal antibodies can be separated and purified by appropriately selecting or combining methods and instruments including, but not limited to, chromatographic columns for affinity chromatography, filtration, ultrafiltration, salt precipitation, dialysis, SDS-polyacrylamide gel electrophoresis, and isoelectric focusing (Antibodies: A Laboratory Manual. Ed Harlow and David Lane, Cold Spring Harbor Laboratory, 1988). Columns used in affinity chromatography include protein A columns and protein G columns. Examples of the protein A column include the Hyper D, POROS, and Sepharose F. F. columns (Amersham Biosciences).

The monoclonal antibody that is capable of binding to an epitope consisting of a continuous amino acid sequence included in positions 101 to 154 or 199 to 270 of SEQ ID NO:226 in the Sequence Listing is preferably a chimeric antibody, humanized antibody, or human antibody, most preferably a human antibody, in view of the low antigenicity it may exhibit when it is administered to a human. Among human antibodies, those wherein the amino acid sequences of the framework regions correspond to amino acid sequences of framework regions from a human germline or a combination of amino acid sequences thereof are preferred. Thus, the present invention relates to a human anti-IL-33 neutralizing monoclonal antibody wherein the amino acid sequences of the framework regions correspond to amino acid sequences of framework regions from a human germline or a combination of amino acid sequences thereof.

Since the framework regions of variable region of such a human anti-IL-33 neutralizing monoclonal antibody comprise amino acid sequences of the human germline framework regions or a combination of amino acid sequences thereof, such a human anti-IL-33 neutralizing monoclonal antibody is characterized by no or significantly low immunogenicity caused by these regions, and also by being capable of binding to IL-33 to inhibit its functions. Thus, when the antibody is used as a pharmaceutical, it is unlikely to induce human anti-human immunoglobulin antibody (HAHA), so that it can avoid clearance in vivo. As a result, the antibody of the invention can attain a prolonged IL-33 neutralizing effect, and is safe because it does not cause inflammation induced by binding with HAHA.

The amino acid sequences of the human germline light-chain and heavy-chain framework regions maybe any amino acid sequence of human germline framework region. Examples of applicable sequence include amino acid sequences encoded by the DNA sequences of heavy-chain and light-chain framework regions of human antibody as registered in the database such as NCBI database (http://www.ncbi.nlm.nih.gov/igblast/showGermline.cgi), and the amino acid sequences of germline framework regions as shown in Table 4. The light-chain variable region may be either a λ chain variable region or κ chain variable region. The light-chain and heavy-chain framework regions of human germline are preferably those which frequently emerge in vivo and are often used. Examples of such a human heavy-chain framework region include the framework regions 1, 2, and 3 of the VH3-23, VH3-30, VH4-39, and VH4-34 germlines and the framework region 4 of the JH4 germline. Examples of human light-chain framework regions which frequently emerge in vivo include the framework regions 1, 2, and 3 of Vλ1-47, Vλ2-14, Vκ3-20, and Vκ1-39 germlines, and the framework region 4 of Jλ2 germline. The heavy-chain framework regions may be composed of any combination of any human heavy-chain framework regions. For example, the framework regions 1 and 2 of VH3-23 germline and the framework region 3 of VH3-30 germline can be selected and used in combination as heavy-chain framework regions. The light-chain framework regions may also be composed of any combination of any human light-chain framework regions.

Preferred amino acid sequences of framework regions of germline in the present invention are those of the framework regions of the VH3-23, VH3-30, JH4, Vλ1-47, and Jλ2 germlines. Specifically, the framework regions preferably have the following amino acid sequences: the amino acid sequence of the light-chain framework region 1 is residues 1 to 22 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 2 is residues 36 to 50 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 3 is residues 58 to 89 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 4 is residues 3 to 12 of SEQ ID NO:401 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 1 is residues 1 to 30 of SEQ ID NO:367 or residues 1 to 30 of SEQ ID NO:368 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 2 is residues 36 to 49 of SEQ ID NO:367 or residues 36 to 49 of SEQ ID NO:368 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 3 is residues 67 to 98 of SEQ ID NO:367 or residues 67 to 98 of SEQ ID NO:368 in the Sequence Listing; and the amino acid sequence of the heavy-chain framework region 4 is residues 5 to 15 of SEQ ID NO:407 in the Sequence Listing. More preferably, the framework regions have the following amino acid sequences: the amino acid sequence of the light-chain framework region 1 is residues 1 to 22 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 2 is residues 36 to 50 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 3 is residues 58 to 89 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 4 is residues 3 to 12 of SEQ ID NO:401 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 1 is residues 1 to 30 of SEQ ID NO:367 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 2 is residues 36 to 49 of SEQ ID NO:367 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 3 is residues 67 to 98 of SEQ ID NO:368 in the Sequence Listing; and the amino acid sequence of the heavy-chain framework region 4 is residues 5 to 15 of SEQ ID NO:407 in the Sequence Listing.

In another embodiment, the present invention relates to an isolated human anti-IL-33 neutralizing monoclonal antibody, wherein the amino acid sequences of a light-chain complementarity-determining region 1 (LCDR1), a light-chain complementarity-determining region 2 (LCDR2), a light-chain complementarity-determining region 3 (LCDR3), a heavy-chain complementarity-determining region 1 (HCDR1), a heavy-chain complementarity-determining region 2 (HCDR2), and a heavy-chain complementarity-determining region 3 (HCDR3) correspond to the combination of amino acid sequences of complementarity-determining regions represented by C1 to C30 in Table 1.

In a preferred embodiment, the human anti-IL-33 neutralizing monoclonal antibody having the combination of complementarity-determining regions represented by C1 to C30 shown in Table 1 has binding ability and neutralizing activity, in particular to mature IL-33 that is capable of binding to an IL-33 receptor to exert activity, e.g., IL-33 (residues 95 to 270), IL-33 (residues 99 to 270), IL-33 (residues 109 to 270), and IL-33 (residues 112 to 270), among IL-33. More preferably, the human anti-IL-33 neutralizing monoclonal antibody having the combination of the complementarity-determining regions represented by C1 to C30 shown in Table 1 has a binding ability to IL-33 (residues 131 to 150).

In a preferred embodiment of the present invention, the combination of amino acid sequences of the complementarity-determining regions provides improved binding ability and/or physical properties of the antibody. In a particularly preferred embodiment, the upper limit of the dissociation rate constant (koff) against human IL-33 is about 3.5×10⁻⁵/sec or lower, more preferably about 2.0×10⁻⁵/sec or lower, more preferably 1.5×10⁻⁵/sec or lower, yet more preferably about 1.0×10⁻⁵/sec or lower, and the lower limit of the dissociation rate constant is, but not limited to, 10⁻⁷/sec or higher, more preferably 10⁻⁶/sec or higher, more preferably about 5×10⁻⁶/sec or higher.

Among human anti-IL-33 neutralizing monoclonal antibodies, more preferred are those which have a low dissociation constant (Kd) against human IL-33. The upper limit of the dissociation constant (Kd) is 10⁻⁹ M or lower, more preferably 10⁻¹⁰ M or lower, yet more preferably 10⁻¹²M or lower, for example. The lower limit of the dissociation rate constant is, but not limited to, preferably 10⁻¹⁴M or higher, more preferably 10⁻¹³ or higher.

The human anti-IL-33 neutralizing monoclonal antibody of the present invention inhibits IL-6 production from HUVEC stimulated with IL-33. In particular, antibodies with higher inhibitory effect are more preferred. Specifically, in a preferred embodiment of the present invention, the human anti-IL-33 neutralizing monoclonal antibody, which attains about 50% or higher, more preferably about 70% or higher, yet more preferably about 90% or higher rate (inhibiting rate) of inhibiting IL-6 production from HUVEC which is stimulated with 100 ng/mL of IL-33 as described below in Example 10, is preferred.

The human anti-IL-33 neutralizing monoclonal antibody of the present invention inhibits production of IL-5, IL-6, and/or IL-13 by KU-812 cells stimulated with IL-33. In particular, antibodies with higher inhibitory effect are more preferred. Specifically, in a preferred embodiment of the present invention, the human anti-IL-33 neutralizing monoclonal antibody which attains the about 30% or higher, more preferably about 50% or higher, yet more preferably about 70% or higher rate (inhibiting rate) of inhibiting production of IL-5, IL-6, and/or IL-13 by KU-812 cells stimulated with 100 ng/mL of IL-33, as described below in Example 11, is preferred.

The human anti-IL-33 neutralizing monoclonal antibody of the present invention inhibits IFN-γ production by human peripheral blood mononuclear cells stimulated with IL-33. In particular, antibodies with higher inhibitory effect are more preferred. Specifically, in a preferred embodiment of the present invention, the human anti-IL-33 neutralizing monoclonal antibody which attains about 80% or higher, more preferably about 90% or higher, yet more preferably about 95% or higher rate of inhibiting IFN-γ production by human peripheral blood mononuclear cells stimulated with 10 ng/mL of IL-33, as described below in Example 12, is preferred.

The human anti-IL-33 neutralizing monoclonal antibody of the present invention inhibits inflammation induced by administration of human IL-33 to a mouse. In particular, antibodies with higher anti-inflammatory effect are more preferred. Specifically, in a preferred embodiment of the present invention, daily intraperitoneal administration of 10 mg/kg of the human anti-IL-33 neutralizing monoclonal antibody for seven days, which attains the rate of inhibiting increases in spleen weight, serum IgA concentration, serum IgE concentration, blood neutrophil count, blood basophil count, blood eosinophil count, and/or serum IL-5 concentration, induced by continuous administration of human IL-33 for seven days at an amount of 0.4 μg/individual, of about 30% or higher, more preferably about 50% or higher, yet more preferably about 80% or higher, as described below in Example 13, is preferred.

The human anti-IL-33 neutralizing monoclonal antibody of the present invention preferably has excellent physical properties. In particular, the human anti-IL-33 neutralizing monoclonal antibody preferably does not show bimodal particle size distribution and exhibits significantly low aggregation property in evaluation by dynamic light scattering. The human anti-IL-33 neutralizing monoclonal antibody of the invention preferably has high interaction parameter (kD), which is an indicator of colloidal stability. For example, the interaction parameter is preferably −12.4 mL/g or higher, more preferably −10 mL/g or higher, yet more preferably −8.5 mL/g or higher.

The human anti-IL-33 neutralizing monoclonal antibody of the present invention preferably has an excellent thermodynamic stability. For example, a preferred antibody exhibits thermodynamic stability such that the folded state of the immunoglobulin domain disappears at a temperature (Tm) of 65° C. or higher, preferably 68° C. or higher, more preferably 70° C. or higher, yet more preferably 73° C. or higher.

The human anti-IL-33 neutralizing monoclonal antibody of the present invention preferably has high antibody stability. The antibody stability can be measured by any common method, e.g., preservation stability test or forced oxidation test. In a preferred embodiment of the present invention, the antibody molecules have a monomer ratio of 90% or higher, more preferably 95% or higher, and have binding activity to the human IL-33 protein of 95% or higher, more preferably 99% or higher, after the preservation stability test at a temperature of 40° C. for four weeks, as described below in Example 21.

As described in Example 22, the human anti-IL-33 neutralizing monoclonal antibody of the present invention preferably has a binding activity of 80% or higher, more preferably 85% or higher, yet more preferably 90% or higher to the human IL-33 protein, after forced oxidation with 1% hydrogen peroxide solution at a temperature of 37° C. for 24 hours.

In view of the foregoing points, the human anti-IL-33 neutralizing monoclonal antibody selected from the combination of complementarity-determining regions represented by C1 to C28 in Table 1 is a preferred antibody. A more preferred embodiment of the present invention is a human anti-IL-33 neutralizing monoclonal antibody having complementarity-determining regions that respectively have amino acid sequences in accordance with a specific combination (C1, C8, C15, C17, or C18 in Table 1).

The human anti-IL-33 neutralizing monoclonal antibody identified by the combination of the amino acid sequences of the respective complementarity-determining regions may have any amino acid sequences of any framework regions in the variable regions, as long as the antigen-binding ability is assured. The respective amino acid sequences of framework regions preferably are amino acid sequences of framework regions from a human germline or a combination of amino acid sequences thereof. The amino acid sequences of framework regions of any germline that is used frequently in vivo in human are more preferred.

In the present invention, the amino acid sequences of the framework regions preferably have the following amino acid sequences: the amino acid sequence of the light-chain framework region 1 is residues 1 to 22 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 2 is residues 36 to 50 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 3 is residues 58 to 89 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 4 is residues 3 to 12 of SEQ ID NO:401 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 1 is residues 1 to 30 of SEQ ID NO:367 or residues 1 to 30 of SEQ ID NO:368 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 2 is residues 36 to 49 of SEQ ID NO:367 or residues 36 to 49 of SEQ ID NO:368 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 3 is residues 67 to 98 of SEQ ID NO:367 or residues 67 to 98 of SEQ ID NO:368 in the Sequence Listing; and the amino acid sequence of the heavy-chain framework region 4 is residues 5 to 15 of SEQ ID NO:407 in the Sequence Listing. More preferably, the framework regions have the following amino acid sequences: the amino acid sequence of the light-chain framework region 1 is residues 1 to 22 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 2 is residues 36 to 50 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 3 is residues 58 to 89 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 4 is residues 3 to 12 of SEQ ID NO:401 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 1 is residues 1 to 30 of SEQ ID NO:367 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 2 is residues 36 to 49 of SEQ ID NO:367 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 3 is residues 67 to 98 of SEQ ID NO:368 in the Sequence Listing; and the amino acid sequence of the heavy-chain framework region 4 is residues 5 to 15 of SEQ ID NO:407 in the Sequence Listing.

Examples of the preferred combinations of the amino acid sequences of the heavy-chain variable regions and the light-chain variable regions in the present invention are shown in Table 2.

A preferred embodiment of the present invention is a human anti-IL-33 neutralizing monoclonal antibody comprising variable regions that respectively have amino acid sequences in accordance with any one of combinations V1 to V28 shown in Table 2.

A more preferred embodiment of the present invention is a human anti-IL-33 neutralizing monoclonal antibody comprising complementarity-determining regions that respectively have amino acid sequences in accordance with a specific combination (V1, V8, V15, V17, or V18 in Table 2).

Depending on the difference in the heavy chain constant regions, human immunoglobulin molecules are categorized into IgG (including IgG1, IgG2, IgG3, and IgG4) having γ heavy chains; IgM having μ heavy chains; IgA (including IgA1 and IgA2) having α heavy chains; IgD having δ heavy chains; and IgE having ε heavy chains. All these types are encompassed in the constant regions of the human anti-IL-33 neutralizing monoclonal antibody of the present invention. Light chains are categorized into κ and λ light chains that differ in the position on chromosome. The light chain in the present invention encompasses both of the two light chains. In production of an antibody pharmaceutical, an antibody having κ light chains is preferred from the perspective of aggregation, but an antibody having λ light chains is also useful, because the λ light chains have a different amino acid sequence from that of the κ chains and have similar diversity to the κ chains. The human anti-IL-33 neutralizing monoclonal antibody of the present invention is preferably IgG having λ light chains and γ heavy chains, more preferably IgG1 having λ light chains and γ1 light chains, from the perspective of the stability in blood.

Since the amino acid sequence of IL-33 is different among animal species, the amino acid sequence of human IL-33 shown in SEQ ID NO:226 in the Sequence Listing is different from that of monkey IL-33 shown in SEQ ID NO:227 in the Sequence Listing. In general, since monkeys are used as experimental animals in pharmacological tests or safety tests of antibody pharmaceuticals, the human anti-IL-33 neutralizing monoclonal antibody of the present invention is preferably further capable of binding to monkey IL-33, and more preferably capable of binding to monkey IL-33 with a binding affinity similar to that with a human IL-33. In a particularly preferred embodiment, the ratio of the koff against human IL-33 versus the koff against monkey IL-33 is within about 20-fold, more preferably within about 10-fold, yet more preferably within about five-fold.

Illustrative examples of the antibody fragment of the present invention include Fab fragments, Fv fragments, F(ab′)₂ fragments, Fab′ fragments, and scFv fragments. These antibody fragments may be bound to non-antibody functional moleculessuch asnon-peptidic polymers, e.g., poly(ethylene glycol) (PEG); radioactive materials; toxins; low-molecular-weight compounds; cytokines; albumin; and enzymes.

The human anti-IL-33 neutralizing monoclonal antibody of the present invention may be bound to an antibody having binding specificity for an antigen other than IL-33, to produce a multispecific antibody such as bispecific antibody. Non-limiting examples of the antigen other than IL-33 include TNF-α, IL-6 receptors, CD3, CD20, α4 integrin, BLys, Thymic Stromal Lymphopoietin, IgE, IL-1, IL-2, IL-4, IL-5, IL-6, IL-13, IL-17, IL-23, and IL-25.

The human anti-IL-33 neutralizing monoclonal antibody and fragments thereof of the present invention may be modified in its amino acid sequence or sugar chain structure in Fc regions, to produce a functionally modified antibody having regulated functions or properties, such as cytotoxic function, complement activation function, and half-life in blood (Kenya Shitara, Journal of the Pharmaceutical Society of Japan, 2009, Vol. 129(1), p. 3; Akiko Ishii et al., Folia Pharmacologica Japonica, 2010, Vol. 136(5), p. 280; Shuhei Hashiguchi et al., SEIKAGAKU (The Journal of Biochemistry), 2010, Vol. 82(8), p. 710; Strohl, Current Opinion in Biotechnology, 2009, vol. 20, p. 685).

The human anti-IL-33 neutralizing monoclonal antibody and antibody fragments thereof in the present invention may be bound to other functional molecule to form a conjugated antibody. For example, novel function can be added by binding a functional molecule, such as non-peptidic polymer, e.g., poly(ethylene glycol) (PEG); radioactive materials; toxins; low-molecular-weight compounds; albumin; cytokines; and enzymes to the antibody.

Other embodiments of the present invention relate to a nucleic acid molecule encoding a protein portion of a human anti-IL-33 neutralizing monoclonal antibody comprising framework regions that have amino acid sequences from germline(s); a vector including the nucleic acid molecule; a host cell including the vector; and a method for production of a human anti-IL-33 neutralizing monoclonal antibody including culturing the host cell.

In a yet another embodiment, the present invention relates to a composition comprising the human anti-IL-33 neutralizing monoclonal antibody described above. Since IL-33 induces inflammation and the like, the human anti-IL-33 neutralizing monoclonal antibody is expected to be applicable to diagnosis, treatment, prevention, or alleviation of a disease associated with IL-33.

Accordingly, in one embodiment, the invention relates to a pharmaceutical composition comprising the human anti-IL-33 neutralizing monoclonal antibody for diagnosis, treatment, prevention, or alleviation of a disease associated with IL-33. In a yet another embodiment, since IL-33 induces cytokines, chemokines, and inflammatory mediators, the present invention relates to an expression inhibitor of the expression for cytokines, chemokines, or inflammatory mediators, comprising the human anti-IL-33 neutralizing monoclonal antibody.

The cytokine to be inhibited by the expression inhibitor for cytokines, chemokines, or inflammatory mediators according to the present invention is one of the IL-33-induced cytokines, including TNF-α, IFN-γ, IL-1β, IL-3, IL-4, IL-5, IL-6, and IL-13 etc. The chemokine to be inhibited with the inhibitor is one of IL-33-induced chemokines, including CXCL2, CCL2, CCL3, CCL6, CCL17, and CCL24, etc. The inflammatory mediator to be inhibited with the inhibitor is one of IL-33-induced inflammatory mediators, including PGD2 and LTB4 etc. A particularly preferred embodiment of the present invention is an expression inhibitor containing a human anti-IL-33 neutralizing monoclonal antibody to inhibit expression of IFN-γ, IL-5, IL-6, or IL-13. More preferably, the inhibitor is an IL-6 production inhibitor.

In another embodiment, the present invention relates to a pharmaceutical composition containing the monoclonal antibody of the present invention. The present invention also relates to a method for diagnosis, treatment, prevention, or alleviation of a disease associated with IL-33, the method comprising administering the monoclonal antibody of the invention; and to use of the monoclonal antibody of the invention for manufacture of a medicament for diagnosis, treatment, prevention, or alleviation of a disease associated with IL-33.

The disease associated with IL-33 include, but not limited to, asthma, atopic dermatitis, urticaria, pollinosis, anaphylactic shock, sinusitis (including eosinophilic sinusitis), allergic encephalomyelitis, hypereosinophilic syndrome, polymyalgia rheumatica, rheumatic heart diseases, multiple sclerosis, arthritis (for example, rheumatoid arthritis, juvenile arthritis, psoriatic arthritis, arthrosis deformans, and Reiter's syndrome), systemic lupus erythematosus (including discoid lupus), pemphigus, pemphigoid, psoriasis, ankylosing spondylitis, hepatitis (for example, autoimmune hepatitis and chronic active hepatitis), inflammatory bowel diseases (for example, ulcerative colitis, Crohn's disease, and gluten-sensitive enteropathy), Sjogren's syndrome, autoimmune hemolytic anemia, autoimmune inflammatory eye diseases, autoimmune neonatal thrombocytopenia, autoimmune neutropenia, autoimmune oophoritis and orchitis, autoimmune thrombocytopenia, autoimmune thyroiditis, multiple myositis, dermatomyositis, myasthenia gravis, adrenergic agonist resistance, alopecia areata (alopecia greata), antiphospholipid syndrome, adrenal autoimmune diseases (for example, autoimmune Addison's disease), celiac sprue-dermatitis, chronic fatigue and immune dysfunction syndrome (CFIDS), cold agglutinin disease, essential mixed cryoglobulinemia, fibromyalgia-fibromyositis, glomerulonephritis (for example, IgA nephropathy), Graves' disease, hyperthyroidism (that is, Hashimoto's thyroiditis), idiopathic thrombocytopenic purpura (ITP), mixed connective tissue disease, Type 1 or immune-mediated diabetes mellitus, pernicious anemia, polychondritis, polyglandular syndrome, stiff-man syndrome, vitiligo, sarcoidosis, polyendocrinopathy, other endocrinopathy, arteriosclerosis, hepatic fibrosis (for example, primary biliary cirrhosis), pulmonary fibrosis (for example, idiopathic pulmonary fibrosis), chronic obstructive pulmonary disease (COPD), scleroderma (including CREST syndrome and Raynaud's phenomenon), tubulointerstitial nephritis, dense deposit disease, acute kidney injury, myocarditis, cardiomyopathy, neuritis (for example, Guillain-Barre syndrome), polyarteritis nodosa, cardiotomy syndrome, chronic inflammatory demyelinating polyneuropathy, IgA neuropathy, lichen planus, Meniere's disease, post-myocardial infarction (post-MI) syndrome, uveitis, uveitis ophthalmia, vasculitis, primary agammaglobulinemia, cancer (for example, brain tumor, laryngeal cancer, lip and oral cancer, hypopharyngeal cancer, thyroid cancer, esophageal cancer, breast cancer, lung cancer, gastric cancer, adrenocortical carcinoma, cancer of the bile duct, gallbladder cancer, liver cancer, pancreatic cancer, bladder cancer, colon cancer, uterine cancer, ovarian cancer, prostate cancer, testicular cancer, chronic lymphocytic leukemia, chronic myelogenous leukemia, Ewing's tumor, Hodgkin's disease, non-Hodgkin lymphoma, melanoma, mesothelioma, and multiple myeloma), infections resistant to clearance by the immune system (for example, severe acute respiratory syndrome (SARS)), lethal cytokine storm associated with virulent influenza infection, and sepsis. The disease associated with IL-33 is preferably asthma, atopic dermatitis, pollinosis, anaphylactic shock, sinusitis (including eosinophilic sinusitis), Crohn's disease, ulcerative colitis, arthritis, systemic lupus erythematosus, pemphigus, pemphigoid, scleroderma, ankylosing spondylitis, hepatic fibrosis (including primary biliary cirrhosis), pulmonary fibrosis, chronic obstructive pulmonary disease (COPD), acute kidney injury, vasculitis, and cancer.

A pharmaceutical composition comprising the human anti-IL-33 neutralizing monoclonal antibody of the present invention may further contain a pharmacologically acceptable carrier, diluent, or excipient, in addition to the human anti-IL-33 neutralizing monoclonal antibody or a salt thereof as the active ingredient. The pharmaceutical composition may further contain an additional active ingredient other than the human anti-IL-33 neutralizing monoclonal antibody of the present invention, for example, an anti-inflammatory agent or immunosuppressive agent. Such a composition is provided in a dosage form suitable for parenteral or oral administration. From the perspective of the use as an antibody pharmaceutical, parenteral administration is preferred. Examples of the parenteral administration include, but are not limited to, intravenous, intraarterial, subcutaneous, topical, intraperitoneal, intramuscular, nasal, ophthalmic, transdermal, transmucosal, intrathecal, rectal, intramuscular, and intracerebral administration.

The pharmaceutical composition may be provided in any dosage form depending on the administration route. Examples of the dosage form include injection, powder, infusion, granule, tablet, and suppository. From the perspective of parenteral administration, the dosage form is preferably injection, infusion, or powder to be dissolved before use. These preparations may further contain any of various adjuvants used in pharmaceuticals. Specific examples of the adjuvant include carriers and other additives, such as stabilizer, preservative, analgesic, and emulsifier.

The human anti-IL-33 neutralizing monoclonal antibody of the present invention may be provided by continuous infusion at intervals of, for example, once per day, week, or month, or one to seven times per year, or by dosing. The dosing may be provided by intravenous, subcutaneous, topical, oral, nasal, rectal, intramuscular, or intraventricular administration, or by inhalation. A preferred dose protocol involves the maximum dose or administration frequency to avoid serious adverse side effects. The total weekly dose is generally at least about 0.05 μg/kg (body weight), more generally at least about 0.2 μg/kg, most generally at least about 0.5 μg/kg, typically at least about 1 μg/kg, more typically at least about 10 μg/kg, most typically at least about 100 μg/kg, preferably at least about 0.2 mg/kg, more preferably at least about 1.0 mg/kg, most preferably at least about 2.0 mg/kg, optimally at least about 10 mg/kg, more optimally at least about 25 mg/kg, most optimally at least about 50 mg/kg.

The human anti-IL-33 neutralizing monoclonal antibody of the present invention is useful in, for example, a diagnostic assay for detection of IL-33 expression in specific cells or tissues, or in blood serum, of a patient with a disease associated with IL-33. For diagnostic application, typically, the human anti-IL-33 neutralizing monoclonal antibody is preferably a conjugated antibody labeled with a detectable moiety.

In another embodiment, the present invention relates to an anti-IL-33 neutralizing monoclonal antibody which competes in binding to IL-33 with an anti-IL-33 neutralizing monoclonal antibody comprising amino acid sequences in accordance with a combination of specific complementarity-determining regions amino acid sequences (C1, C8, C15, C17, or C18 in Table 1) or in accordance with a combination of specific variable region amino acid sequences (V1, V8, V15, V17, or V18 in Table 2).

The anti-IL-33 neutralizing monoclonal antibody which competes in binding to IL-33 with an anti-IL-33 neutralizing monoclonal antibody comprising amino acid sequences in accordance with a combination of specific complementarity-determining regions amino acid sequences or in accordance with a combination of specific variable regions amino acid sequences can be obtained as follows: anti-IL-33 antibodies are produced by a genetic engineering technique, e.g., phage display, or the hybridoma technique; and the produced anti-IL-33 antibodies are screened by the surface plasmon resonance (SPR) technique as described below, for example.

Biotinylated human IL-33 protein (4 μg/mL) as ligand is loaded on an avidin-immobilized sensor chip to be immobilized thereon at an amount equivalent to 1300 to 1600 RU. Any anti-IL-33 antibody (15 μg/mL) is then loaded as an analyte thereon, so as to bind to the human IL-33 protein immobilized on the sensor chip. The process is repeated for several times until all the human IL-33 protein molecules immobilized on the sensor chip is bound by the anti-IL-33 antibody (saturation). Then the binding level at saturation (saturation binding level 1) is determined.

The same experiment is carried out with a human anti-IL-33 neutralizing monoclonal antibody comprising complementarity-determining regions that respectively have amino acid sequences in accordance with a specific combination or a human anti-IL-33 neutralizing monoclonal antibody comprising variable regions that respectively have amino acid sequences in accordance with a specific combination according to the invention, and the binding level at saturation (saturation binding level 2) is determined.

After the saturation of the human IL-33 protein on the sensor chip with the human anti-IL-33 neutralizing monoclonal antibody comprising complementarity-determining regions that respectively have amino acid sequences in accordance with a specific combination or the human anti-IL-33 neutralizing monoclonal antibody comprising variable regions that respectively have amino acid sequences in accordance with a specific combination according to the invention, any anti-IL-33 antibody (15 μg/mL) is loaded as an analyte. It is confirmed whether the analyte exhibits additional binding with the human IL-33 protein that has been saturated with the human anti-IL-33 neutralizing monoclonal antibody comprising complementarity-determining regions that respectively have amino acid sequences in accordance with a specific combination or the human anti-IL-33 neutralizing monoclonal antibody comprising variable regions that respectively have amino acid sequences in accordance with a specific combination according to the invention.

If any anti-IL-33 antibody can exhibit additional binding with the human IL-33 protein that has been saturated with the human anti-IL-33 neutralizing monoclonal antibody comprising complementarity-determining regions that respectively have amino acid sequences in accordance with a specific combination or the human anti-IL-33 neutralizing monoclonal antibody comprising variable regions that respectively have amino acid sequences in accordance with a specific combination according to the invention, while maintaining its saturation binding level 1 calculated above, then the anti-IL-33 antibody is determined to be “not competitive.” If the anti-IL-33 antibody cannot exhibit additional binding with the human IL-33 protein that has been saturated with the human anti-IL-33 neutralizing monoclonal antibody comprising complementarity-determining regions that respectively have amino acid sequences in accordance with a specific combination or the anti-IL-33 neutralizing monoclonal antibody comprising variable regions that respectively have amino acid sequences in accordance with a specific combination according to the invention, then the anti-IL-33 antibody is determined to be “competitive.” If the anti-IL-33 antibody can exhibit additional binding with the human IL-33 protein that has been saturated with the human anti-IL-33 neutralizing monoclonal antibody comprising complementarity-determining regions that respectively have amino acid sequences in accordance with a specific combination or the anti-IL-33 neutralizing monoclonal antibody comprising variable regions that respectively have amino acid sequences in accordance with a specific combination according to the invention but the additional binding level is lower than the saturation binding level 1 with a significant difference, then the antibody is determined to be “competitive.” The significant difference can be determined by a common statistical method (for example, Student's t-test). The level of significance is set to equal to or less than 5% or 1%.

The anti-IL-33 neutralizing monoclonal antibody which competes in binding to IL-33 with a human anti-IL-33 neutralizing monoclonal antibody comprising amino acid sequences in accordance with a combination of specific complementarity-determining regions amino acid sequences or in accordance with a combination of specific variable regions amino acid sequences may be an antibody from any animal, for example, mouse, human, rat, rabbit, goat, or camel, and may also be a chimeric antibody or humanized antibody produced by combining such antibodies.

The anti-IL-33 neutralizing monoclonal antibody which competes in binding to IL-33 with the human anti-IL-33 neutralizing monoclonal antibody comprising amino acid sequences in accordance with a combination of specific complementarity-determining regions amino acid sequences or in accordance with a combination of specific variable regions is preferably a chimeric antibody, humanized antibody, or human antibody, most preferably human antibody.

The anti-IL-33 neutralizing monoclonal antibody which competes in binding to IL-33 with the human anti-IL-33 neutralizing monoclonal antibody comprising amino acid sequences according to a combination of specific complementarity-determining regions amino acid sequences or a combination of specific variable regions amino acid sequence includes antibody fragments. Examples of the antibody fragment include Fab fragments, Fv fragments, F(ab′)₂ fragments, Fab′ fragments, and scFv fragments. Antibody fragments bound with PEG or the like are preferred.

The method for production of the anti-IL-33 neutralizing monoclonal antibody and the like of the present invention will be now described. The human anti-IL-33 neutralizing monoclonal antibody can be prepared through a genetic engineering technique, through incorporation of a DNA sequence which contains sequences encoding a desired combination of complementarity-determining regions and a combination of framework regions and encodes light-chain and heavy-chain variable regions into an expression vector; transformation of the expression vector into a host cell; and then culture of the host cell (see, for example, Borrebaeck C. A. K. and Larrick J. W. THERAPEUTIC MONOCLONAL ANTIBODIES, Published in the United Kingdom by MACMILLAN PUBLISHERS LTD, 1990). Alternatively, DNA sequences which respectively encode full-length heavy chain and full-length light chain can be produced through linkage of a DNA sequence encoding light-chain constant region to a DNA sequence encoding light-chain variable region and linkage of a DNA sequence encoding heavy-chain constant region to a DNA sequence encoding heavy-chain variable region. The combination of DNA sequences respectively encoding the full-length heavy chain and full-length light chain of a preferred human anti-IL-33 neutralizing antibody of the present invention include, for example, that of IgG1 having λ light chain as shown in Table 5. If the antibody is produced with an animal cell through a genetic engineering technique, the C-terminal lysine residue may be deleted. For this reason, the three nucleotides “aag” in the 3′ terminus of the nucleic acid sequence of the heavy chain shown in Table 5 (SEQ ID NOS:254 to 277 in the Sequence Listing) may be deleted from each heavy-chain nucleic acid sequence.

TABLE 5 The following SEQ ID Nos. show the SEQ ID Nos. in the Sequence Listing Combination Light Chain Heavy Chain IGN1 SEQ ID No. 228 SEQ ID No. 254 IGN2 SEQ ID No. 229 SEQ ID No. 255 IGN3 SEQ ID No. 230 SEQ ID No. 256 IGN4 SEQ ID No. 230 SEQ ID No. 257 IGN5 SEQ ID No. 230 SEQ ID No. 258 IGN6 SEQ ID No. 231 SEQ ID No. 259 IGN7 SEQ ID No. 230 SEQ ID No. 260 IGN8 SEQ ID No. 232 SEQ ID No. 261 IGN9 SEQ ID No. 233 SEQ ID No. 262 IGN10 SEQ ID No. 234 SEQ ID No. 262 IGN11 SEQ ID No. 235 SEQ ID No. 262 IGN12 SEQ ID No. 236 SEQ ID No. 262 IGN13 SEQ ID No. 237 SEQ ID No. 262 IGN14 SEQ ID No. 238 SEQ ID No. 262 IGN15 SEQ ID No. 239 SEQ ID No. 262 IGN16 SEQ ID No. 240 SEQ ID No. 263 IGN17 SEQ ID No. 241 SEQ ID No. 264 IGN18 SEQ ID No. 242 SEQ ID No. 265 IGN19 SEQ ID No. 243 SEQ ID No. 266 IGN20 SEQ ID No. 244 SEQ ID No. 267 IGN21 SEQ ID No. 245 SEQ ID No. 268 IGN22 SEQ ID No. 246 SEQ ID No. 269 IGN23 SEQ ID No. 247 SEQ ID No. 270 IGN24 SEQ ID No. 248 SEQ ID No. 271 IGN25 SEQ ID No. 249 SEQ ID No. 272 IGN26 SEQ ID No. 250 SEQ ID No. 273 IGN27 SEQ ID No. 251 SEQ ID No. 274 IGN28 SEQ ID No. 252 SEQ ID No. 275 IGN29 SEQ ID No. 230 SEQ ID No. 276 IGN30 SEQ ID No. 253 SEQ ID No. 277

The production system for preparing antibodies may be any of in vitro production systems. Examples of the in vitro production system include eukaryotic cells, e.g., animal cells, plant cells, or fungal cells; and prokaryotic cells, e.g., bacterial cells such as Escherichia coli and Bacillus subtilis. Examples of the applicable animal cells include mammalian cells, e.g., generally used cells, such as CHO, COS, myeloma, BHK, HeLa, Vero, 293, NSO, Namalwa, and YB2/0 cells; and insect cells and plant cells can also be used. The 293 and CHO cells are preferred.

If the monoclonal antibody is produced in an in vitro production system as described above, the DNA encoding the heavy chain and the DNA encoding the light chain may be incorporated into separate expression vectors to co-transform the host, or may be incorporated together into a single expression vector to transform the host (see WO 94/11523). Examples of the preferred vector applicable to animal cells include, but are not limited to, pConPlus, pcDM8, pcDNA I/Amp, pcDNA3.1, and pREP4.

The antibody thus produced can be purified to homogeneity. The antibodies can be separated and purified by any ordinary method used for separation and purification of proteins. For example, the antibodies can be separated and purified by appropriately selecting or combining methods and instruments including, but not limited to, chromatographic columns for affinity chromatography, filtration, ultrafiltration, salt precipitation, dialysis, SDS-polyacrylamide gel electrophoresis, and isoelectric focusing (Antibodies: A Laboratory Manual. Ed Harlow and David Lane, Cold Spring Harbor Laboratory, 1988). Columns used in affinity chromatography include protein A columns and protein G columns. Examples of the protein A column include the Hyper D, POROS, and Sepharose F. F. columns (Amersham Biosciences).

The human anti-IL-33 neutralizing monoclonal antibody of the present invention can be bound to any antibody that have binding specificity for other antigen than IL-33 to produce a multispecific antibody, such as bispecific antibody. Several chemical methods of producing the bispecific antibody have been already known well (Nisonoff, A. et al., Archives of biochemistry and biophysics., 1961, Vol. 90, p. 460-462, Brennan, M. et al., Science, 1985, Vol. 299, pp. 81-83). In such methods, two different antibodies are each hydrolyzed with an enzyme, and then disulfide bonds in the heavy chains of the antibody are cleaved with a reducing agent, followed by mixing of the two heterologous antibodies and re-oxidization of the mixture. A bivalent antibody is thereby produced. Preparation of antibodies using a crosslinker, such as glutaraldehyde or carbodiimide, has also been recently disclosed (Japanese Patent Application Laid-Open Publication No. 2-1556). Several genetic engineering techniques for producing multispecific antibodies such as bispecific antibodies have already been established in the art. A desired bispecific antibody can be prepared by linking antigen-binding regions of two different monoclonal antibodies in tandem in accordance with a DVD-Ig method (Wu et al., Nature Biotechnology 25(11), 1290(2007)), or by modifying Fc region of an antibody to combine heavy chains of two different antibodies that are capable of binding to different antigens in accordance with the ART-Ig method (Kitazawa et al., Nature Medicine 18(10), 1570(2012)), for example.

A functionally modified form of the human anti-IL-33 neutralizing monoclonal antibody of the present invention or a conjugated antibody containing the antibody of the invention can be prepared by a method described below, for example. If the human anti-IL-33 neutralizing monoclonal antibody of the invention is produced in CHO host cells knocked out for the α1,6-fucosyltransferase (FUT8) gene, the antibody has a decreased fucose content on the sugar chains, resulting in an increased cytotoxic function, while an antibody produced in CHO host cells transfected with the FUT 8 gene has a low cytotoxic function (WO 2005/035586, WO 2002/31140, and WO 00/61739). The complement activation function of the antibody can be regulated by modification of its Fc region via a modification in amino acid residues (U.S. Pat. Nos. 6,737,056, 7,297,775, and 7,317,091). The half-life of the antibody in blood can be prolonged with an Fc region variant having increased binding ability to FcRn, one of Fc receptors (Shuhei Hashiguchi et al., SEIKAGAKU (The Journal of Biochemistry), 2010, Vol. 82(8), p. 710). Such functionally-modified antibodies can be produced by genetic engineering techniques.

The human anti-IL-33 neutralizing monoclonal antibody of the present invention can be bound to other functional molecules to produce a conjugated antibody. For example, if PEG is bound as a functional molecule to an antibody, non-limiting examples of the PEG include PEG with a molecular weight of 2000 to 100000 Da, more preferably 10000 to 50000 Da. The PEG may be either linear or branched. PEG can be bound to an N-terminal amino group of an amino acid in the antibody by using NHS active group. Examples of radioactive materials used as a functional molecule include ¹³¹I, ¹²⁵I, ⁹⁰Yr, ⁶⁴Cu, ⁹⁹Tc, ⁷⁷Lu, ²¹¹At and the like. Radioactive materials can be directly bound to the antibody by any method such as chloramine T method. Examples of toxins used as a functional molecule include bacterial toxins (for example, diphtheria toxin), phytotoxins (for example, ricin), low-molecular-weight toxins (for example, geldanamycin), maytansinoid, and calicheamicin. Examples of the low-molecular-weight compound used as a functional molecule include daunomycin, doxorubicin, methotrexate, mitomycin, neocarzonostatin, vindesine, and fluorescent dyes such as FITC. Examples of enzymes used as a functional molecule include luciferase (for example, firefly luciferase and bacterial luciferase; U.S. Pat. No. 4,737,456), malate dehydrogenase, urease, peroxidase (for example, horseradish peroxidase (HRPO)), alkaline phosphatase, β-galactosidase, glucoamylase, lysozyme, saccharide oxidase (for example, glucose oxidase, galactose oxidase, and glucose-6-phosphate dehydrogenase), heterocyclic oxidase (for example, uricase and xanthine oxidase), lactoperoxidase, and microperoxidase. Examples of the linker used in chemical binding of toxin, low-molecular weight compound or enzyme include divalent radicals (for example, alkylene, arylene, and heteroarylene), linkers represented by —(CR₂)_(n)O(CR₂)_(n)— (where R is any substituent group), repeating units of alkoxy (for example, polyethyleneoxy, PEG, and polymethyleneoxy), alkylamino (for example, polyethyleneamino and Jeffamine™), and diacid esters and amides (including succinates, succinamides, diglycollates, malonates, and capramides). Several methods for chemical modification to bind the functional molecule have been already established in the art (D. J. King., Applications and Engineering of Monoclonal antibodies., 1998 T. J. International Ltd, Monoclonal Antibody-Based Therapy of Cancer., 1998 Marcel Dekker Inc; Chari et al., Cancer Res., 1992 Vol. 152:127; Liu et al., Proc Natl Acad Sci USA., 1996 Vol. 93:8681).

The anti-IL-33 neutralizing monoclonal antibody which competes in binding to IL-33 with a human anti-IL-33 neutralizing monoclonal antibody comprising a combination of specific complementarity-determining regions amino acid sequences (C1, C8, C15, C17, or C18 in Table 1) or a combination of specific variable regions amino acid sequences (V1, V8, V15, V17, or V18 in Table 2) may be an antibody from any animal, for example, mouse antibody, human antibody, rat antibody, rabbit antibody, goat antibody, or camel antibody, and may also be a chimeric antibody or humanized antibody produced by combining such antibodies. Such anti-IL-33 neutralizing monoclonal antibodies can be produced by any known method including, for example, hybridoma technique, phage display technique, and genetic engineering techniques. In particular, the antibody is preferably produced by a genetic engineering method.

A chimeric antibody can be produced by ligating a DNA which encodes variable regions of a non-human antibody to a DNA which encodes constant regions of a human antibody, incorporating the resulting DNA into an expression vector, which is then transformed into a host cell for expression of the antibody of interest (see EP 125023 and WO 92/19759).

A humanized antibody can be produced by ligating a DNA which encodes complementarity-determining regions (CDR) of a non-human antibody to a DNA which encodes the remaining regions of a human antibody, and incorporating the resulting DNA into an expression vector, which is then transformed into a host cell

A human antibody can be prepared through the process described in the Examples below. The human antibody can also be prepared by any technique such as trioma technique, human B CELLS hybridoma technique (Kozbor et al., 1983 Immunol Today 4: p. 72) and EBV hybridoma technique for producing a human monoclonal antibody (Cole et al., 1985, MONOCLONAL ANTIBODIES AND CANCER THERAPY, Alan R. Liss, Inc., p. 77). The human antibody may also be produced by immunizing a transgenic mouse introduced a human antibody gene with an antigen protein to produce a hybridoma. Examples of the transgenic mouse include HuMab (registered trademark) mouse (Medarex), KMTM mouse (Kirin Pharma), KM (FCγRIIb-KO) mouse, and Veloclmmune mouse (Regeneron Pharmaceuticals, Inc.).

In another embodiment, the present invention relates to an artificial antibody which competes in binding to IL-33 with the anti-IL-33 neutralizing monoclonal antibody comprising amino acid sequences in accordance with a combination of a specific complementarity-determining regions amino acid sequences (C1, C8, C15, C17, or C18 in Table 1) or a specific variable regions amino acid sequences (V1, V8, V15, V17, or V18 in Table 2). As the artificial antibody, for example, the tenth unit in the human fibronectin type III domain (FNfn10) can be used. An artificial antibody capable of binding to a desired target can be produced by introducing mutation in the BC, DE, and/or FG loops of the unit. Besides the extracellular domain of fibronectin, Kunitz domain of serine protease inhibitor and peptides such as ankyrin and lipocalin can be used as the artificial antibody. These artificial antibodies can be produced by a genetic engineering technique involving introduction of a vector containing a nucleic acid molecule which encodes the peptide into Escherichia coli, yeast, or animal cells, culture of the host cells, and then recovery and purification of the culture supernatant.

The artificial antibody can be selected by searching a random sequence library including random combinations of amino acids for a low-molecular-weight peptide molecules which are capable of binding specifically to the epitope of the present invention, such as an antibody, instead of use of the amino acid sequence of a specific protein or a part thereof as described above (for example, Hipolito et al., Current Opinion in Chemical Biology, 2012 Vol. 16: 196; Yamagishi et al., Chemistry & Biology, 2011 Vol. 18: 1562). Such a peptide can also be produced by any chemical synthetic method such as a fluorenylmethyloxycarbonyl technique or t-butyloxycarbonyl technique, instead of a genetic engineering technique.

[Combination of Sequences of Antibody]

The combinations C1 to C30 shown in Table 1, i.e. combinations of amino acid sequences for complementarity-determining regions; the combinations V1 to V30 shown in Table 2, i.e. combinations of amino acid sequences for variable regions; the combinations CN1 to CN30 shown in Table 5, i.e. the combinations of nucleic acid sequences for complementarity-determining regions; and the combinations IGN1 to IGN30 shown in Table 5, i.e. combinations of nucleic acid sequences, of the human anti-IL-33 neutralizing monoclonal antibody described in the specification respectively correspond to identical clone sequences. The correspondence between the sequences is shown in Table 6. For example, the complementarity-determining regions of the clone A10-1C04 respectively correspond to the six amino acid sequences of complementarity-determining regions represented by the combination C1, and the combination of amino acid sequences of the complementarity-determining regions may be respectively encoded by the six nucleic acid sequences of the combination CN1. The clone comprises heavy-chain and light-chain variable regions respectively corresponding to the two amino acid sequences of the combination V1. The amino acid sequences of λ light chain and γ heavy chain, including the variable regions, of the combination V1 are respectively encoded by the two nucleic acid sequences of the combination IGN1.

TABLE 6 Heavy Variable Chain/Light CDR Region CDR Chain (Amino (Amino (Nucleic (Nucleic Clone Acids Acids Acids Acid name Sequence) Sequence) Sequence) Sequence) A10-1C04 C1 V1 CN1 IGN1 A12-1E04 C2 V2 CN2 IGN2 A12-1H04 C3 V3 CN3 IGN3 A12-1H08 C4 V4 CN4 IGN4 A13-1F05 C5 V5 CN5 IGN5 A13-1F07 C6 V6 CN6 IGN6 A13-1G05 C7 V7 CN7 IGN7 A23-1A05 C8 V8 CN8 IGN8 A25-2D01 C9 V9 CN9 IGN9 A25-2B02 C10 V10 CN10 IGN10 A25-2E04 C11 V11 CN11 IGN11 A25-2C06 C12 V12 CN12 IGN12 A25-2C07 C13 V13 CN13 IGN13 A25-2H11 C14 V14 CN14 IGN14 A25-2C02 C15 V15 CN15 IGN15 A25-3G05 C16 V16 CN16 IGN16 A25-3H04 C17 V17 CN17 IGN17 A26-1F02 C18 V18 CN18 IGN18 A26-2A05 C19 V19 CN19 IGN19 A26-2B01 C20 V20 CN20 IGN20 A27-1A06 C21 V21 CN21 IGN21 A27-1C06 C22 V22 CN22 IGN22 A28-1C08 C23 V23 CN23 IGN23 A28-1G07 C24 V24 CN24 IGN24 A28-2C06 C25 V25 CN25 IGN25 A28-2F01 C26 V26 CN26 IGN26 A28-2G07 C27 V27 CN27 IGN27 A28-2H06 C28 V28 CN28 IGN28 A00-0070 C29 V29 CN29 IGN29 A00-0036 C30 V30 CN30 IGN30

EXAMPLES

The present invention will now be described in more details by way of Examples, which should not be construed to limit the invention, unless otherwise indicated.

Example 1: Preparation of Anti-IL-33 Antibodies and Identification of Epitope Peptides [Preparation of Antibodies]

A human IL-33 protein was immunized to an animal to produce a hybridoma from the splenic cells of the immunized animal, and the monoclonal antibody was thereby prepared. The RNA was extracted from the splenic cells of the immunized animal to produce a library of antibodies of the animal. Antibodies capable of binding to the human IL-33 protein were cloned from such a library and the human naive antibody library by phage display technique. Eight anti-IL-33 monoclonal antibodies (Antibodies A to H) were thereby prepared.

[Peptide Array Scanning]

In order to identify the epitope for the resulting IL-33 antibodies, peptide array scanning was carried out to confirm the binding of each antibody to each of the partial peptides (20 residues in length) of human IL-33. Peptides consisting of 20 amino acids were synthesized, each shifted by 10 amino acids within the sequence spanning valine at N-terminal position 101 (V101) and threonine at N-terminal position 270 (T270) to cover the major part of mature human IL-33 molecules. Sixteen peptides (PEP11 to PEP26) in total were thereby synthesized. The sequence and position of each of these peptides are shown in FIG. 12.

Each peptide was N-terminally biotinylated, and was immobilized as ligand onto a NeutrAvidin sensor chip of a surface plasmon resonance (SPR) system (ProteOn XPR36, available from Bio-Rad Laboratories, Inc.). As positive control, the mature human IL-33 (residues 112 to 270) was N-terminally linked with the Avitag sequence, and was biotinylated by biotin ligase reaction specific for the AviTag sequence. The resulting protein (hIL-33) as a ligand was immobilized onto the SPR sensor chip. Each test antibody, the human IL-33 receptor protein (recombinant human ST2 Fc chimera) (ALX-201-367-0050, available from Enzo Life Science, Inc.), or buffer (0.05% Tween20/PBS) alone was then loaded as an analyte onto the sensor chip containing the ligand immobilized thereon (antibody concentration: 10 μg/ml; flow rate: 100 μl/min), to allow them to bind to the ligand. After washing, the amount of analyte (amount of antibody) bound to the ligand on the sensor chip was measured as RU value. The results are shown in FIG. 2.

The antibodies were designated, in sequence, in accordance with the position of epitope in the human IL-33 protein: the antibody to the epitope located at the most N-terminal portion was designated “Antibody A”. The Antibodies A and B bound to PEP12, the Antibodies C and D bound to PEP14, the Antibody E bound to both PEP16 and PEP17, the Antibody F bound to PEP24, and the Antibodies G and H bound to PEP26. A commercially available anti-human IL-33 polyclonal antibody (AF3625, available from R&D Systems, Inc.) bound to most of the 16 human IL-33 peptides studied. The human IL-33 receptor (ST2) bound to the human IL-33 protein, but substantially did not bind to the human IL-33 peptides (PEP11 to PEP26). The experiment failed to identify what portion of the IL-33 was significant for the binding with ST2. No binding with the ligand was observed in the buffer alone or murine IgG (MAB002, available from R&D Systems, Inc.). The tested antibodies were compared for the binding ability to hIL-33 (residues 112 to 270). The descending order of the binding ability of the antibody to hIL-33 (residues 112 to 270) was Antibody G, Antibody H, Antibody D, Antibody E, Antibody B, Antibody A, Antibody C, and Antibody F.

Example 2: Evaluation of IL-33 Neutralizing Activity of Anti-IL-33 Monoclonal Antibodies-1

The Antibodies A, B, E, and F were measured for the IL-33 neutralizing activity, based on the inhibitory effect on the binding between immobilized human ST2 and humanIL-33 as indicator. Recombinant human ST2 Fc chimera (ALX-201-367-0050, available from Enzo Life Science, Inc.) diluted with phosphate buffered saline (PBS) was dispensed into a 96-well microplate (Nunc™, #442404) (1 μg/mL, 50 μL/well), and was left to stand overnight at a temperature of 4° C. The following day, the microplate was washed once with 1% BSA-containing PBS (PBS-B), and PBS-B was added to the microplate (250 μL/well) for blocking at a room temperature for two hours. After the blocking, a mixed solution of each test antibody diluted with PBS-B (final concentration: 10 μg/mL) and a recombinant human IL-33 protein (ILC0701, available from ATGen Co. Ltd) (final concentration: 1 μg/mL) was added to the microplate (50 μL/well), and the solution was incubated at a room temperature for two hours. After the microplate was washed with 0.1% Tween 20-containing PBS (PBS-T) for five times, goat anti-human IL-33 antibody (AF3625, available from R&D Systems, Inc.; final concentration: 1 μg/mL; 50 μL/well) diluted with PBS-B was subsequently added to the microplate, and the solution was then incubated at a room temperature for one hour. After the microplate was washed with PBS-T for five times, the HRP-labeled rabbit anti-goat IgG antibody (Invitrogen:61-1620, 50 μL/well) diluted to 2000-fold with PBS-B was added, and the solution was incubated at a room temperature for one hour. After the microplate was washed with PBS-T for five times, SureBlue™ TMB Microwell Peroxidase Substrate (KPL:52-00-01, 50 μL/well) was added. The solution was allowed to react at a room temperature for 20 minutes, and then the reaction was stopped with TMB Stop Solution (KPL: 50-85-05, 50 μL/well). The difference between the absorbance at wavelength of 450 nm and that at wavelength of 620 nm was measured with a microplate reader (SpectraMax 190, available from Molecular Devices, LLC.). A sample was prepared by replacing the human IL-33 with human IL-1β (PeproTech, 200-01B) (final concentration: 1 μg/mL), and the results observed in this sample was set as background. The inhibitory effect of each antibody on the binding of ST2 and IL-33 (competitive inhibition percentage in IL-33/ST2 binding system) was determined by calculating the percentage of inhibition (%) of binding by each antibody relative to the binding observed in a sample containing the human IL-33 alone (final concentration: 1 μg/mL). According to the results, the Antibody A (epitope: PEP12) exhibited 66% inhibition, the Antibody B (epitope: PEP12) exhibited 55% inhibition, the Antibody E (epitopes: PEP16 and PEP17) exhibited 0% inhibition, and the Antibody F (epitope: PEP24) exhibited 39% inhibition. All of the four antibodies tested, except for the Antibody E, (i.e. Antibodies A, B and F) exhibited inhibition percentage of 30% or higher at final concentration of 10 μg/mL.

TABLE 8 Competitive Inhibition Percentage in IL-33/ST2 binding Epitope system [%] Antibody A PEP12 66 Antibody B PEP12 55 Antibody E PEP16-17 <0 Antibody F PEP24 39

Example 3: Evaluation of the IL-33 Neutralizing Effect of Anti-IL-33 Monoclonal Antibody-2

Each of the test antibodies (Antibodies A to H) was measured for the IL-33 neutralizing activity based on the inhibitory effect on human IL-33-induced IL-6 production in normal human umbilical vein endothelial cells (HUVEC) (CLC2517A, available from LONZA Group Ltd.) as indicator. The HUVEC cells were inoculated in a 96-well microplate (IWAKI, MT4940-010) (6×10³/0.1 mL/well), and cell confluence was confirmed. Each anti-IL-33 antibody (final concentration: 10 μg/mL) and recombinant human IL-33 (ILC0701, available from ATGen Co. Ltd; final concentration: 100 ng/mL) were added (0.2 mL/well) to a medium (EGM-2 medium (CLCC-3156 and CLCC-4176, available from LONZA Group Ltd.)), and the solution was incubated at a temperature of 37° C. for 24 hours. After 24 hours, the IL-6 concentration in the medium was measured with a commercially available ELISA kit (EH2IL6, available from Thermo Scientific). After collection of the medium, cell viability was measured with a cell counting kit (345-06463, available from Dojindo Molecular Technologies, Inc.), so as to confirm that the inhibitory effect on IL-6 production was not caused by a decrease in the viable cell count. In order to determine the IL-33 neutralizing activity of each test antibody (inhibition % of IL-6 production in HUVEC system), the percentage of inhibition (%) of IL-6 production relative to the IL-6 production caused by the treatment with recombinant human IL-33 alone was calculated. According to the results, the Antibody A (epitope: PEP12) exhibited 51% inhibition, the Antibody B (epitope: PEP12) exhibited 48% inhibition, the Antibody C (epitope: PEP14) exhibited 33% inhibition, the Antibody D (epitope: PEP14) exhibited 38% inhibition, the Antibody E (epitope: PEP16 to PEP17) exhibited 0% inhibition, the Antibody F (epitope: PEP24) exhibited 38% inhibition, the Antibody G (epitope: PEP26) exhibited 48% inhibition, and the Antibody H (epitope: PEP26) exhibited 56% inhibition. All of the eight antibodies tested, except for the Antibody E, exhibited inhibition percentage of 30% or higher (Table 9). Among these antibodies, those that were capable of binding to an epitope consisting of a sequence selected from the group consisting of positions 111 to 130, 131 to 150, 231 to 250, and 251 to 270 of SEQ ID NO:1 in the Sequence Listing exhibited significant increases in the neutralizing activity, at the antibody concentration of 3, 10, and 30 μg/mL (for example, the Antibody D exhibited inhibition of 23%, 42%, and 61%, respectively); the results demonstrate that such epitopes are suitable for producing an antibody having an antagonistic action.

TABLE 9 Inhibition Percentage of IL-6 production in Epitope HUVEC system [%] Antibody A PEP12 51 Antibody B PEP12 48 Antibody C PEP14 33 Antibody D PEP14 38 Antibody E PEP16-17 <0 Antibody F PEP24 38 Antibody G PEP26 48 Antibody H PEP26 56

The Antibody E bound to hIL-33 (FIG. 2), but did not exhibit functional neutralizing ability (Tables 8 and 9). PTL 2 (WO 2008/132709) discloses three epitopes: epitope 1 (positions 155 to 198), epitope 2 (positions 165 to 188), and epitope 3 (positions 175 to 178). The present experiments revealed that these epitopes had a sequence overlapping with the epitope peptides for the Antibody E (positions 151 to 180) which was confirmed not to have IL-33 neutralizing activity. These results suggest that antibodies to the epitopes disclosed in PTL 2 cannot sufficiently inhibit the binding of IL-33 with ST2, its receptor, and has no or very low IL-33 neutralizing activity.

Theoretically, possible causes for the absence of IL-33 neutralizing activity in the Antibody E would be inferiority of the epitope and insufficiency of affinity. The Antibodies D, G, and H tended to have lower avidity with hIL-33, as compared to the Antibody E, but clearly exhibited IL-33 neutralizing activity. In view of the existence of such clones, it is believed that the absence of the neutralizing activity is probably not caused by insufficiency of affinity. Based on such findings, the four epitopes currently found by the inventors (PEP12, PEP14, PEP24, and PEP26) are believed to be functional epitopes when the purpose is neutralization of IL-33 cytokine, in that the avidity between IL-33 and antibodies for the epitopes is relevant to the IL-33 neutralizing activity of the antibodies, unlike the epitopes disclosed in PTL 2. An antibody that is capable of binding to a functional epitope has high antagonistic effect on IL-33, while an antibody that is capable of binding to a non-functional epitope has a low or no antagonistic effect on IL-33.

Example 4: Mapping of Epitope Peptides to the Conformation of Human IL-33

In order to identify the interfacial atoms (the atom of IL-33 located at the atomic distance of 5 Å or less from a component atom of ST2, when the two atoms are in the closest proximity) which would be a preferred epitope for production of an antibody with antagonistic effect, the four epitope peptides were mapped on the conformation of the human IL-33/human ST2 complex. The X-ray crystallographic structure of the human IL-33/human ST2 complex (Research Collaboratory for Structural Bioinformatics: PDB ID 4KC3) lacked a partial structure of the IL-33 protein, and thus it was impossible to show the positions of all the epitope peptides identified in the invention. The inventors thus created homology model based on the X-ray crystallographic structure (4KC3) as template (FIG. 3; Discovery Studio 3.5 (available from Accelrys) was used), and the epitope peptides (PEP12, PEP14, PEP24, and PEP26) corresponding to the antibodies which exhibited neutralizing activity in the present experiments were mapped on the model (FIG. 4 to FIG. 7). In FIG. 4 to FIG. 7, human IL-33 and epitope peptides are shown in dark grey, and ST2 bound to the IL-33 or epitope peptides are shown in light grey. The interfacial atoms are highlighted by indicating them with larger spheres in order to clearly show the position of interface between the IL-33 protein and IL-33 receptors on the IL-33 protein surface. The results demonstrated that these epitope peptides (PEP12, PEP14, PEP24, and PEP26) each have amino acids containing interfacial atoms. Examples of amino acids containing the interfacial atoms include P118, I119, T120, Y122, L123, R124, S125, L126, S127, Y129, and N130 of PEP12; D131, Q132, S133, T135, A137, L138, E139, S142, Y143, E144, I145, Y146, E148, D149, and L150 of PEP14; D244, N245, and H246 of PEP24; and K266, L267, S268, and E269 of PEP26. A preferred epitope to which an antibody with antagonistic effect is to bind specifically is believed to have amino acids containing the interfacial atoms.

Example 5: Preparation of Human Anti-IL-33 Antibodies (Parental Clones)

Using a human scFv phage display library (n-CoDeR, available from Biolnvent International AB) (Soderlind et al., Nature biotechnology, 2000 Vol. 18(8), p. 852), two different parental clones (scFv) (it indicates that the molecular form is scFv; hereinafter, represented in the same way) were prepared (clones designated A00-0070 and A00-0036), which were capable of binding to mature IL-33 (residues 112 to 270) to inhibit the binding of IL-33 to ST2 and inhibit IL-33 activity, when they were analyzed based on the IL-33-dependent IL-6 production in normal human umbilical vein endothelial cells (HUVEC) as described below. The antibodies were sequenced to obtain their base sequences and amino acid sequences of light-chain and heavy-chain variable regions. A00-0070 and A00-0036 respectively had amino acid sequences of light-chain and heavy-chain variable regions in accordance with the combinations V29 and V30, respectively, shown in Table 2.

Example 6: Determination of Amino Acid Substitution for Improving Complementarity-Determining Regions

The complementarity-determining regions of two parental clones were modified by Fab ribosome display and Fab phage display techniques, for increased affinity with IL-33 and improved physical properties (i.e. reduced surface hydrophobicity and consequent decreased aggregation and increased solubility) of the clones. The complementarity-determining regions were modified in the following two steps: the first step of determination of single-amino acid substitutions for improving the affinity with IL-33 and the physical properties; and the second step of determination of combinations of such single-amino acid substitutions (Fujino et al., Biochem. Biophys. Res. Commun., 2012 Vol. 428(3), p. 395).

A Fab ribosome display vector was constructed based on the light-chain and heavy-chain variable regions of the two parental clones, and was then subjected to multistep PCR reactions involving site-directed mutagenesis PCR and overlap extension PCR, to construct a comprehensive library of single-amino acid substitution variants covering all single-amino acid substitutions within the six complementarity-determining regions (LCDR1, LCDR2, LCDR3, HCDR1, HCDR2, and HCDR3) of the antibody. Amino acid residues respectively were replaced with 20 natural amino acids in total. The Fab ribosome display process (Fujino et al., Biochem. Biophys. Res. Commun., 2012 Vol. 428(3), p. 395) was performed in a reconstituted cell-free translation system, PURE system (PUREfrex, available from GeneFrontier Corporation) (Shimizu et al., Nature Biotechnology, 2001, Vol. 19(8), p. 751) over the comprehensive library of single-amino acid substitution variants. Library selection was repeated several rounds using a recombinant human IL-33 protein (ILC0701, available from ATGen Co. Ltd) as bait, to enrich the library. Each of the clones (Fab) (“clone (Fab)” indicates that the clone has a molecular form of Fab; hereinafter, the same representation is used) contained in the library before the enrichment (i.e. just after construction) and after the enrichment was sequenced with a next-generation sequencer (Roche, 454) to determine the base sequences of the light-chain and heavy-chain variable regions. Sequence data with several thousands of reads of the library before and after the enrichment was obtained to calculate the frequency of each of all variants having single-amino acid substitution in the complementarity-determining regions. The ratio of change between the frequencies in the library before and after the enrichment (i.e. enrichment ratio) was calculated for each of all single-amino acid substitution variants. The magnitude of the enrichment ratio in the library enrichment was used as an indicator to determine some single-amino acid substitutions assumed to be useful for improving affinity with the human IL-33 protein. Based on the total number of the single-amino acid substitutions and the distribution on the amino acid sequence, positions where the amino acid substitutions were to be introduced were determined for construction of the custom library in the second step.

In the parental clone A00-0070, introduction of amino acid substitutions in the following positions was determined: asparagine at position 12 of LCDR1 (SEQ ID NO:2 in the Sequence Listing); glutamine at position 4 of LCDR2 (SEQ ID NO:11 in the Sequence Listing); serine at position 2, tyrosine at position 3, and serine at position 6 of LCDR3 (SEQ ID NO:23 in the Sequence Listing); aspartic acid at position 1 and asparagine at position 5 of HCDR1 (SEQ ID NO:43 in the Sequence Listing), serine at position 4, serine at position 5, serine at position 7, and isoleucine at position 9 of HCDR2 (SEQ ID NO:64 in the Sequence Listing). In the parental clone A00-0036, introduction of amino acid substitutions in the following positions was determined: asparagine at position 9 and asparagine at position 13 of LCDR1 (SEQ ID NO:6 in the Sequence Listing); arginine at position 6 and leucine at position 7 of LCDR2 (SEQ ID NO:20 in the Sequence Listing); alanine at position 1, alanine at position 9, and valine at position 10 of LCDR3 (SEQ ID NO:40 in the Sequence Listing); asparagine at position 1 of HCDR1 (SEQ ID NO:47 in the Sequence Listing); serine at position 4, serine at position 5, serine at position 6, serine at position 7, tyrosine at position 8, isoleucine at position 9, tyrosine at position 10, tyrosine at position 11, aspartic acid at position 13, and lysine at position 16 of HCDR2 (SEQ ID NO:64 in the Sequence Listing); and glycine at position 2, histidine at position 5, and aspartic acid at position 6 of HCDR3 (SEQ ID NO:78 in the Sequence Listing).

For improving physical properties of the clones, homology models of the two parental clones were generated with a protein structure analysis program (Discovery Studio, available from Accelrys) to predict regions with high surface hydrophobicity within the complementarity-determining regions, and then to determine positions to be substituted for reducing the surface hydrophobicity of the predicted regions. In the parental clone A00-0070, introduction of amino acid substitutions in the following positions was determined: tyrosine at position 3 of LCDR3 (SEQ ID NO:23 in the Sequence Listing); and serine at position 7 and isoleucine at position 9 of HCDR2 (SEQ ID NO:64 in the Sequence Listing). In the parental clone A00-0036, introduction of amino acid substitutions in the following positions was determined: arginine at position 6 and leucine at position 7 of LCDR2 (SEQ ID NO:20 in the Sequence Listing); and serine at position 7, tyrosine at position 8, and isoleucine at position 9 of HCDR2 (SEQ ID NO:64 in the Sequence Listing). Based on the data on enrichment ratio obtained in the analysis of mutation using the comprehensive library of single-amino acid substitution variants, the amino acid substitutions assumed to be useful for reducing the surface hydrophobicity without affecting the binding ability to the human IL-33 protein was determined among these sites.

Example 7: Production of a Human Anti-IL-33 Antibody with Modified Complementarity-Determining Regions

Two or more of the useful amino acid substitutions for improvements in affinity and physical properties as described above were combined to design a full-scale custom library for modifying the complementarity-determining regions. Vectors for Fab ribosome display and Fab phage display processes were constructed. The Fab ribosome display vector was then subjected to multistep PCR reactions involving site-directed mutagenesis PCR and overlap extension PCR, and the Fab phage display vector was used as a template to perform site-specific mutagenesis by Kunkel mutagenesis method (Fellouse et al., J. Mol. Biol. 2007 Vol. 373, p. 924), to construct a custom library for improvement of complementarity-determining regions, in which the positions in the complementarity-determining regions were randomized based on the design described above. The Fab ribosome display and Fab phage display processes were performed. Library selection was repeated for several rounds using Human IL-33 protein and cynomolgus monkey IL-33 protein (GenBank: EHH57404; spanning from Ser residue 112 to Glu residue 269 in SEQ ID NO:227 in the Sequence Listing) as bait, to enrich the library. In the latter half of the rounds, negative selection was performed with hydrophobic column carriers such as octyl sepharose (GE Healthcare) or phenyl sepharose (GE Healthcare) before allowing the binding with the IL-33 proteins, so as to enrich the Fab having high affinity with the IL-33 protein and low surface hydrophobicity.

The recombinant proteins used as bait were prepared by the following process. A gene sequence encoding the mature humanIL-33 (residues 112 to 270) and mature cynomolgus monkey IL-33 (residues 112 to 269 of SEQ ID NO:227 in the Sequence Listing) was N-terminally linked with 6His tag-AviTag, and the resulting sequence was inserted into pET30a(−) to construct an expression vector to prepare the recombinant protein. Escherichia coli BL21 (DE3) strain including the expression vector was pre-cultured in 5 mL of LB medium, and then 1 mL of the pre-culture solution was inoculated into 50 mL of expression medium (Overnight Express, available from Merck Millipore Corporation; supplemented with kanamycin). The bacterial cells were cultured for protein expression for 18 hours at 200 rpm and at a temperature of 30° C. The bacterial cells were collected and washed, and then were bacteriolyzed with BagBuster (Novagen), and the supernatant was recovered. The 6His-AviTag-linked cynomolgus monkey IL 33 (residues 112 to 269) contained in the supernatant was purified with Ni-NTA Agarose (available from QIAGEN), and was biotinylated. The biotin modification specific for the AviTag portion was introduced with a commercially available biotin ligase (BirA, available from Avidity LLC).

The library after the enrichment was used to construct a library of Escherichia coli secreting and expressing Fab. The culture supernatants of several hundreds of clones of Escherichia coli were subjected to measurement of dissociation rate constant (koff) by surface plasmon resonance (SPR) (ProteOn XPR36, available from Bio-Rad Laboratories, Inc.). The biotinylated human IL-33 protein (4 μg/mL) and cynomolgus monkey IL-33 protein (4 μg/mL) were loaded as ligands on a sensor chip (NLC sensor chip, available from Bio-Rad Laboratories, Inc.), to immobilize the human IL-33 protein at an amount equivalent to 1300 to 1600 RU, and the cynomolgus monkeyIL-33 protein at an amount equivalent to 1100 to 1500 RU. The culture supernatant of Escherichia coli was then loaded thereon as analyte to obtain a sensorgram with association phase of one minute and dissociation phase of 10 to 30 minutes. The sensorgram was subjected to interspot correction and blank correction using an SPR data analysis program (ProteOn Manager v3.1.0, available from Bio-Rad Laboratories, Inc.), and then values of koff were determined by off-rate analysis of Langmuir model.

Among the clones (Fab) with modified complementarity-determining regions, 28 clones (corresponding to V1 to V28 in Table 2) that had an increased affinity with human IL-33 protein and had binding ability to cynomolgus monkey IL-33 protein were selected to be analyzed in higher-level tests in Example 8 and following Examples. As shown in Table 10, the selected clones (Fab) had higher affinity (i.e. low koff value) with the human and cynomolgus monkey IL-33 proteins, as compared to their parental clones (Fab). These clones had no amino acid substitution within the framework regions in the variable regions. Even two variants have an identical single-amino acid substitution in the complementarity-determining regions, the effect of improving affinity is different between a single-amino acid substitution variant and a variant with two or more amino acid substitutions. For such a reason, some amino acid substitutions were frequent in the sequences of the 28 clones for higher-level evaluation, although the enrichment ratio of single-amino acid substitution variants containing such substitutions was low in the first step in the comprehensive library of single-amino acid substitution variants, and vice versa.

TABLE 10 Cynomolgus Combination Human IL-33 Cynomolgus Monkey IL-33 of Variable Human IL-33 Binding Monkey IL-33 Binding Clone Name Region koff (/sec) Amount (RU) koff (/sec) Amount (RU) A10-1C04 V1 1.00E−05 26 1.65E−04 20 A12-1E04 V2 2.19E−05 414 5.58E−05 512 A12-1H04 V3 1.94E−05 94 4.83E−05 131 A12-1H08 V4 1.00E−05 77 7.51E−05 102 A13-1F05 V5 1.32E−05 127 5.79E−05 171 A13-1F07 V6 1.00E−05 112 3.48E−05 151 A13-1G05 V7 1.00E−05 59 5.45E−05 80 A23-1A05 V8 1.58E−05 52 2.61E−05 54 A25-2D01 V9 1.00E−05 950 1.00E−05 832 A25-2B02 V10 1.00E−05 256 1.00E−05 237 A25-2E04 V11 1.27E−05 195 1.00E−05 199 A25-2C06 V12 1.36E−05 480 1.59E−05 501 A25-2C07 V13 3.41E−05 334 7.37E−05 330 A25-2H11 V14 1.22E−05 534 2.57E−05 492 A25-2C02 V15 1.00E−05 930 1.00E−05 839 A25-3G05 V16 1.34E−05 135 2.02E−05 143 A25-3H04 V17 1.00E−05 162 1.00E−05 179 A26-1F02 V18 1.00E−05 96 1.00E−05 100 A26-2A05 V19 1.00E−05 153 1.00E−05 147 A26-2B01 V20 1.00E−05 364 1.00E−05 363 A27-1A06 V21 1.00E−05 306 1.00E−05 320 A27-1C06 V22 1.00E−05 294 1.14E−05 304 A28-1C08 V23 1.00E−05 156 1.00E−05 144 A28-1G07 V24 1.00E−05 165 1.05E−05 173 A28-2C06 V25 1.00E−05 123 1.00E−05 134 A28-2F01 V26 1.00E−05 289 1.00E−05 258 A28-2G07 V27 1.00E−05 289 1.14E−05 259 A28-2H06 V28 1.00E−05 349 1.00E−05 317 A00-0070 V29 4.27E−03 571 5.22E−03 270 A00-0036 V30 1.52E−02 78 3.47E−02 59

Example 8: Preparation of IgG Antibodies

DNAs which respectively encode amino acid sequences of light and heavy chains of the seven human anti-IL-33 antibody clones prepared above (A10-1C04, A23-1A05, A25-2C02, A25-3H04, A26-1F02, A00-0070, and A00-0036) were each inserted downstream of a CMV promoter to construct an expression vector for mammalian cells for expression of IgG. The DNA sequences of the light chain of the clones were those shown in SEQ ID NOs:228, 232, 239, 241, 242, 230, and 253, respectively, in the Sequence Listing. The DNA sequences of the heavy chain of the clones were those shown in SEQ ID NOs:254, 261, 262, 264, 265, 276, and 277, respectively, in the Sequence Listing. Each of the expression vectors was transfected into FreeStyle 293-F cells (Life Technologies) using a transfection reagent NeoFection-293-1 (available from Astec Co., Ltd.). After the transfection, the cells were cultured for five days, and then the culture supernatant was collected. Stable cell lines of CHO cells were established with GS system (available from LONZA Group Ltd.) using a pConPlus vector and CHO K1SV cells. The stable cell lines of CHO cells were cultured, starting from a concentration of 0.3×10⁶ cells/mL using WAVE Bioreactor SYSTEM 20/50 EHT (GE Healthcare), and the culture solution containing secreted IgG was collected. IgG was purified from the culture supernatant by affinity chromatography using AKTA explorer 100 (GE Healthcare) and a Protein A resin (HiTrap MabSelect SuRe, available from GE Healthcare). IgG bound to the protein A resin was eluted with an elution buffer with a pH of 3.2, and then the eluate was immediately neutralized to have an approximately neutral pH, and then was dialyzed with PBS (with a pH of 7.2). IgG after the purification with the protein A column was further purified with CHT (ceramic hydroxyapatite Type I resin, available from Bio-Rad Laboratories, Inc.) to increase the purity. IgG bound to CHT was eluted with NaCl concentration gradient. Fractions of interest were collected and then were dialyzed with PBS (with pH of 7.2). The antibodies obtained by this purification process are referred to as “neutral-purified antibodies”.

Another purification process was also performed, which further involves the step of washing with six-column volume of 100 mM sodium carbonate buffer (with a pH of 11.0) for six minutes prior to the step of elution of IgG from the protein A resin in the purification process described above. The antibodies obtained from this purification process are referred to as “alkaline-purified antibodies”. Recovery rates of the individual alkaline-purified antibodies after each step are shown in Table 11. The alkaline-purified antibodies after purification were concentrated by centrifugal ultrafiltration with VIVASPIN Turbo15 30000 MWCO (Sartorius AG).

TABLE 11 Collection Rate by Collection Collection Protein A Rate by CHT Rate by Purification Purification condensation Clone Name (%) (%) (%) A10-1C04 87 90 79 A23-1A05 64 86 72 A25-3H04 91 91 101 A25-2C02 64 80 65 A26-1F02 93 82 108

Example 9: Affinity with IL-33 Protein

Each test antibody (IgG) (“antibody (IgG)” indicates an antibody having a molecular form of IgG; hereinafter, the same representation is used) was analyzed to confirm the affinity with the human IL-33 protein by measuring dissociation constant (Kd) between each test antibody and the human IL-33 protein in PBS by kinetic exclusion assay (KinExA) (KinExA3200, available from Sapidyne Instruments, Inc.). Mixture samples of a test antibody and a human IL-33 protein (ILC0701, available from ATGen Co. Ltd) were prepared. The human IL-33 protein was titrated to a constant concentration of test antibody (final concentration: several tens of pM to several hundreds of pM) over a wide concentration range of the human IL-33 protein (so that it covered the concentrations of the human IL-33 protein resulting from 12-step serial doubling dilutions, i.e. one- to 2048-fold, with the upper limit of final concentration set to several nM to several tens of nM). The mixture samples were incubated at a room temperature until the antigen-antibody reaction reached equilibrium. After the reaction reached equilibrium, the percentage of free anti-IL-33 antibody in each sample was analyzed using KinExA3200. The values of Kd were calculated by fitting the plot of percentages of anti-IL-33 antibody not bound to the human IL-33 protein (vertical axis) and concentrations of antigen (horizontal axis) to a theoretical formula, using a KinExA data analysis program (KinExA Pro Software v3.5.3, available from Sapidyne Instruments, Inc.). Beads for capturing the anti-IL-33 antibody were prepared by suspending 50 mg of Azlactone beads (Sapidyne) in 1 mL of coating solution (10 μg/mL human IL-33 protein (ILC0701, available from ATGen Co. Ltd), 50 mM sodium carbonate at pH of 9.6) and incubating the solution at a room temperature for one hour. The antibody for detection used was anti-human F(ab)′2-DyLight649 (Jackson, 309-495-006). As shown in Table 12, the antibodies with modified complementarity-determining regions (A10-1C04, A23-1A05, A25-2C02, A25-3H04, A26-1F02) exhibited affinity with the human IL-33 protein of Kd=231 pM at the lowest (A23-1A05) and Kd=720 fM at the highest (A25-2C02), in the case where they were evaluated in the form of neutral-purified antibodies.

Each of the alkaline-purified antibodies was analyzed to confirm the affinity with the human IL-33 protein (residues 112 to 270) (ILC0701, available from ATGen Co. Ltd) or full-length human IL-33 protein with KinExA instrument (Table 12), as in the evaluation described above. The affinity with the human IL-33 protein (residues 112 to 270) was as follows: A10-1C04 exhibited affinity of Kd=100.3 pM; A23-1A05 exhibited affinity of Kd=195.3 pM; A25-2C02 exhibited affinity of Kd=700 fM; A25-3H04 exhibited affinity of Kd=7.7 pM; and A26-1F02 exhibited affinity of Kd=5.3 pM. The affinity with the full-length human IL-33 protein was as follows: A10-1C04 exhibited Kd=179.8 pM, and A26-1F02 exhibited affinity of Kd=10.4 pM.

The recombinant protein used as ligand was prepared by the following process. The gene sequence encoding the full-length human IL-33 protein was N-terminally linked with NusA tag-6His tag-TEV Protease cleaving sequence, and the resulting sequence was inserted into pET30a(+) to construct an expression vector to prepare the recombinant protein. Escherichia coli BL21 (DE3) strain including the expression vector was pre-cultured, and the bacterial cells were inoculated into 50 mL of LB medium at a density of OD=0.5, and were cultured with shaking for four hours at a temperature of 37° C. After four hours, the culturing temperature was changed to 13° C., and the cells were cultured with shaking for 30 minutes. IPTG was added to a final concentration of 0.1 mM, and the cells were further cultured with shaking for 72 hours at a temperature of 13° C. The Escherichia coli expressing the full-length IL-33 was thereby obtained. The Escherichia coli expressing the full-length IL-33 was bacteriolyzed with BugBuster Master Mix (Novagen), and then the supernatant fraction was collected by centrifugal separation. The supernatant fraction was then subjected to IMAC purification with HisTrap FF Crude column (GE Healthcare) and then to anion exchange purification with CaptoQ Impress column (GE Healthcare), to increase the protein purity. Each sample after the anion exchange was concentrated by centrifugal ultrafiltration using VIVASPIN6 (5,000 MWCO). To 1750 μL of the concentrate, 100 μL of Turbo TEV protease (Nacalai Tesque, Inc.) and 4.5 μL of 1M DTT were added. The resulting solution was incubated at a temperature of 4° C. to cleave the NusTag and HisTag. After the cleavage of the tags, the solution was passed through a Ni Sepharose Excel column (GE Healthcare) in order to remove the NusTag and Turbo TEV protease (fused with HisTag) in the solution, and the flow-through fraction was collected. DTT was added to the flow-through fraction to a final concentration of 3.3 mM, and the resultant was used as the full-length human IL-33 protein in the measurement with KinExA.

TABLE 12 Purification Method Neutral-Purified Antibody Alkaline-Purified Antibody Human IL-33 Human IL-33 Human IL-33 Ligand (Residues 112-270) (Residues 112-270) (Full-Length) A10-1C04 166*    100.3 179.8 A23-1A05 231    195.3 NCW A25-3H04 5.38 7.7 NCW A25-2C02 0.72 0.7 NCW A26-1F02 10.8  5.3  10.4 *The numerical value in the table means dissociation constant of anti IL-33 monoclonal antibody (IgG) purified by a specific method for each ligand

Example 10: Evaluation of In Vitro Neutralizing Activity Against Human IL-33 in HUVEC

Each test antibody (IgG) was evaluated for in vitro neutralizing activity against human IL-33, based on IL-33-dependent IL-6 production by HUVEC as indicator. A commercially available polyclonal anti-IL-33 antibody (AF3625, available from R&D Systems, Inc.) was used as a positive control. HUVECs (CLC2517A, available from LONZA Group Ltd.) were suspended in an EGM-2 medium (CLCC-3156 and CLCC-4176, available from LONZA Group Ltd.), and were inoculated in a 96-well microplate (IWAKI) (6×10³/well), and the cell density was confirmed to be confluent. A mixed solution of each anti-IL-33 antibody (final concentration: 1 μg/mL (about 6.7 nM)) and a recombinant human IL-33 protein (ILC0701, available from ATGen Co. Ltd) (final concentration: 100 ng/mL (about 5 nM)) was added to the medium, and the resulting solution was incubated at a temperature of 37° C. for 24 hours. The medium was then collected, and the IL-6 concentration in the culture supernatant was measured with a commercially available ELISA kit (EH2IL6, available from Thermo Scientific). Cell viability after the collection of the medium was also measured with a cell counting kit (345-06463, available from Dojindo Molecular Technologies, Inc.), to confirm that the inhibitory effect on IL-6 production was not caused by a decrease in the viable cell count. The percentage of inhibition (%) of IL-6 production relative to the IL-6 production caused by the treatment with IL-33 alone was calculated to determine the IL-33 neutralizing activity of each test antibody. In the evaluation of neutral-purified form, A10-1C04 exhibited 67% inhibition, A23-1A05 exhibited 74% inhibition, A25-2C02 exhibited 96% inhibition, A25-3H04 exhibited 97% inhibition, A26-1F02 exhibited 96% inhibition, A00-0070 exhibited 4% inhibition, and A00-0036 exhibited −2% inhibition. The results demonstrate that the clones exhibited strong neutralizing activity, while the parental clones exhibited very low neutralizing activity. When the concentration was increased to 10 μg/mL, the parental clones exhibited moderate neutralizing activity: A00-0070 exhibited 42% inhibition, and A00-0036 exhibited 38% inhibition. The commercially available polyclonal antibody (AF3625, available from R&D Systems, Inc.) exhibited 30% inhibition, indicating moderate neutralizing activity, when it was added to a final concentration of 1 μg/mL.

As well as the evaluation above, a mixed solution of each alkaline-purified test antibody (final concentration: 0.1 to 10 μg/mL (about 0.67 to 67 nM)) and the recombinant human IL-33 (ILC0701, available from ATGen Co. Ltd) (final concentration: 100 ng/mL (about 5 nM)) was added to the HUVECs. The inhibitory effect on IL6 production relative to the IL-6 production caused by the treatment with IL-33 alone was calculated (IC₅₀ value) to determine the neutralizing activity of the antibody. The results were as follows: A10-1C04 had IC₅₀=0.35 μg/mL; A23-1A05 had IC₅₀=0.27 μg/mL; A25-2C02 had IC₅₀=0.19 μg/mL; A25-3H04 had IC₅₀=0.21 μg/mL; and A26-1F02 had IC₅₀=0.23 μg/mL.

Further, a mixture solution of each alkaline-purified antibody (final concentration: 0.1 to 3 μg/mL) and recombinant cynomolgus monkey IL-33 (prepared as in Example 7 and was used without biotinylation) (final concentration: 100 ng/mL) was added to the HUVECs. The inhibitory effect on IL6 production relative to the IL-6 production caused by the treatment with IL-33 alone was calculated (IC₅₀ value) to determine the neutralizing activity of the antibody. A10-1C04 had IC₅₀=0.43 μg/mL, and was confirmed to neutralize human IL-33 and cynomolgus monkey IL-33 at a similar level.

Example 11: Evaluation of In Vitro Neutralizing Activity Against Human IL-33 in KU-812 Cells

Each test antibody (IgG) was evaluated for in vitro neutralizing activity against human IL-33, based on IL-33-dependent production of IL-5, IL-6, and IL-13 by KU-812 cells as indicator. A commercially available polyclonal anti-IL-33 antibody (AF3625, available from R&D Systems, Inc.) was used as a positive control. Human basophil cell line, KU-812 cells (ECACC, EC90071807) were inoculated in a 96-well microplate (Falcon) (1×10⁴/well). A mixed solution of each test antibody (final concentration: 3 μg/mL (about 20 nM)) and a recombinant human IL-33 protein (ILC0701, available from ATGen Co. Ltd) (final concentration: 100 ng/mL (about 5 nM)) was added to the medium, and the resulting solution was incubated at a temperature of 37° C. for 24 hours. The concentrations of IL-5, IL-6, and IL-13 in the RPMI-1640 medium containing 10% FBS were measured using Human IL-5 Flex set, Human IL-6 Flex set, and Human IL-13 Flex set of BDTM Cytometric Bead Array (BD Biosciences). Cell viability after the collection of the medium was also measured with a cell counting kit (345-06463, available from Dojindo Molecular Technologies, Inc.), so as to confirm that the inhibitory effect on the production of IL-5, IL-6, and IL-13 was not caused by a decrease in the viable cell count. In the evaluation of neutral-purified form, A26-1F02 inhibited production of IL-5, IL-6, and IL-13 by 70%, 82%, and 72%, respectively, in this evaluation system. The results indicate that A26-1F02 exhibited stronger neutralizing activity on production of all the cytokines, as compared to the commercially available polyclonal antibody (it exhibited 47%, 51%, and 41% inhibition, respectively).

As in the evaluation above, a mixed solution of each alkaline-purified test antibody (final concentration: 100 to 0.01 μg/mL (about 667 to 0.067 nM)) and the recombinant human IL-33 (ILC0701, available from ATGen Co. Ltd) (final concentration: 3 ng/mL (about 0.15 nM)), human IL-3 (PeproTech, 200-03; final concentration: 10 ng/mL (about 0.67 nM)), and human complement C5a (C5788, available from Sigma-Aldrich Co. LLC.) (final concentration: 1 nM) was added to the KU-812 cells. The resulting solution was incubated at a temperature of 37° C. for 24 hours. The concentrations of IL-5 and IL-13 in the RPMI-1640 medium containing 10% FBS were measured. Cell viability after the collection of the medium was also measured with a cell counting kit, so as to confirm that the inhibitory effect on the production of IL-5 and IL-13 was not caused by a decrease in the viable cell count. In this evaluation system, alkaline-purified test antibodies (A10-1C04, A23-1A05, A25-2C02, A25-3H04, and A26-1F02) each exhibited an inhibitory effect of 50% or higher inhibition against production of IL-5 and IL-13 at a final concentration of 1 μg/mL.

Example 12: Evaluation of In Vitro Neutralizing Activity Against Human IL-33 in Human Peripheral Blood Mononuclear Cells

Each test antibody (IgG) was evaluated for in vitro neutralizing activity against human IL-33, based on IL-33-dependent IFN-γ production by human peripheral blood mononuclear cell (PBMC) as indicator. A commercially available polyclonal anti-IL-33 antibody (AF3625, available from R&D Systems, Inc.) was used as a positive control. PBMCs were prepared and were inoculated in a 96-well microplate (2×10⁵/well), and a recombinant human IL-12 (Wako Pure Chemical Industries, Inc.) was added (final concentration: 10 ng/mL) to the microplate. A mixture of each test antibody and a recombinant human IL-33 protein (10 ng/mL) was added to the microplate, and the resulting solution was incubated at a temperature of 37° C. for 48 hours. The culture supernatant was then collected, and the IFN-γ production level in the medium was measured with AlfaLISA TM human IFN-γ immunoassay kit (PerkinElmer Inc.) to evaluate IL-33 neutralizing activity. In this evaluation system, when the alkaline-purified antibodies were allowed to act at a final concentration of 10 μg/mL, the inhibition percentages were as follows: A10-1C04 exhibited 96.9% inhibition, A23-1A05 shows 97.5% inhibition, A25-2C02 exhibited 98.75% inhibition, A25-3H04 exhibited 97.9% inhibition, and A26-1F02 exhibited 98.25% inhibition.

Example 13: Evaluation of Effects on Inflammation Induced by Intraperitoneal Administration of Human IL-33

Intraperitoneal administration of human IL-33 to mice induced various inflammatory changes, i.e. increases in blood IgE, IgA, and IL-5, and blood neutrophil count, blood eosinophil count, and blood basophil count, and an increase in splenic cells (an increase in spleen weight), and pathological changes in various mucosal organs. Based on these changes as indicators, anti-inflammatory action in vivo of test antibody (IgG) was evaluated.

Human IL-33 protein (R&D Systems, 3625-IL-010) was intraperitoneally administered to male C57BL6 (six- to eight-weeks-old) (Charles River Laboratories International, Inc.) at a dose of 0.4 μg/individual for seven days (day 0 to day 6). The test antibody (IgG) was also administered intraperitoneally for seven days (day 0 to day 6). Seven days after initiation of the administration (day 7), the animals administered with PBS instead of human IL-33 protein (represented as “vehicle” in the figures) had a mean spleen weight of 76±4 mg, while the animals administered with IL-33 protein had a mean spleen weight of 90±7 mg. The animals intraperitoneally administered with 10 mg/kg (represented as “mpk” in the figures) of human control IgG (MP Biomedicals, 55908) in addition to the IL-33 protein had a mean spleen weight of 93±4 mg, while the animals intraperitoneally administered with 10 mg/kg of the neutral-purified antibody A26-1F02 in addition to the IL-33 protein had a mean spleen weight of 66±3 mg.

The alkaline-purified antibody was then evaluated. The alkaline-purified antibody was subcutaneously administered only once (sc, one shot), on the day before the administration of the human IL-33 protein (Day −1) and the evaluation was performed. Seven days after initiation of the administration (day 7), the animals administered with PBS instead of human IL-33 protein had a mean spleen weight of 70 mg, while the animals subcutaneously administered only once with the human control IgG (10 mg/kg) in addition to the IL-33 protein had a mean spleen weight of 152 mg. Contrarily, the animals subcutaneously administered with A25-3H04 (1, 3, 5, and 10 mg/kg) in addition to the IL-33 protein had spleen weights of 143, 106, 109, and 78 mg, respectively, as shown in FIG. 8. The results indicated that A25-3H04 exhibited dose-dependent inhibition of increase in spleen weight caused by inflammation. In addition to the anti-inflammatory effects on the spleen weight, A25-3H04 was confirmed to have anti-inflammatory effects on increases in serum IgA concentration, serum IgE concentration, blood neutrophil count, blood basophil count, and blood eosinophil count, and serum IL-5 concentration, which had been caused by administration of human IL-33 (FIG. 8). These results confirm that A25-3H04 exhibits inhibitory effect on the inflammatory response induced in vivo by IL-33. The blood A25-3H04 concentration in mice was measured seven days after the initiation of the administration (day 7). The measured concentrations in the animals administered with the antibody at doses of 1, 3, 5, and 10 mg/kg, respectively, were 0.6, 3.7, 6.5, and 20.3 μg/ml.

Other test antibodies (IgG) were also evaluated for in vivo anti-inflammatory effects by subcutaneous administration in accordance with the same protocol (10 mg/kg). As a result, the animals subcutaneously administered with human control IgG had a mean spleen weight of 181 mg, the animals subcutaneously administered with alkaline-purified antibody (A10-1C04, A23-1A05, A25-2C02, or A26-1F02) in addition to administration of IL-33 protein had mean spleen weights of 82 mg, 92 mg, 100 mg, and 77 mg, respectively, as shown in FIG. 9. The results indicate that each antibody inhibited increase in spleen weight caused by inflammation. In addition to the anti-inflammatory effects on the spleen weight, each alkaline-purified antibody (A10-1C04, A23-1A05, A25-2C02, and A26-1F02) was confirmed to have anti-inflammatory effects on increases in serum IgA concentration, serum IgE concentration, blood neutrophil count, blood basophil count, and blood eosinophil count, which had been caused by administration of human IL-33 protein (FIG. 9). These results confirm that these antibodies (A10-1C04, A23-1A05, A25-2C02, and A26-1F02), in addition to A25-3H04, also exhibit inhibitory effects on the inflammatory response induced in vivo by IL-33.

Example 14: Evaluation of Effects on Pulmonary Disorders Induced by Intratracheal Administration of Human IL-33

Mice are intratracheally administered with human IL-33 protein, and then the bronchoalveolar lavage fluid (BALF) is collected from the mice. Increases in the total cell count, eosinophil count, and neutrophil count are observed in the BALF, and mucosal hyperplasia in the tracheal epithelium is observed. Production of cytokines, such as IL-4, IL-5, IL-6, and IL-13, is also observed in the BALF. Effects of each test antibody on the pulmonary disorders can be evaluated by intraperitoneal, subcutaneous, or intravenous administration of the test antibody (IgG) to the system.

Example 15: Evaluation of Effects on Airway Hyperresponsiveness Induced by Intranasal Administration of Human IL-33

Intranasal administration of an IL-33 protein induces airway hyperresponsiveness to subsequently inhaled methacholine. Effects of the test antibody on airway hyperresponsiveness can be evaluated by intraperitoneal, subcutaneous, or intravenous administration of the test antibody (IgG) to the evaluation system.

Example 16: Evaluation of Effects of IL-33 on Human IL-33-Knockin Mice

Administration of Dermatophagoides antigen or papain to human IL-33-knockin mice by nasal dripping or intratracheal administration induces airway inflammation. The BALF collected from the mice exhibits an increased total cell count in the BALF. Regarding airway inflammation induced by Dermatophagoides antigen or papain, it is known that protease activity of Dermatophagoides antigen or papain causes release of IL-33 from the airway epithelial cells (Oboki et al., Proceedings of the National Academy of Sciences of the United States of America, 2010, vol. 107, p 18581). Effects of each test antibody on the protease-induced airway inflammation and on IL-33-induced in vivo can be evaluated by intraperitoneal, subcutaneous, or intravenous administration of the test antibody (IgG) to the evaluation system.

Example 17: Evaluation of Anti-Inflammatory Effects on Sepsis Model Intraperitoneally Administered with LPS

Intraperitoneal administration of LPS to human IL-33-knockin mice induces sepsis (Oboki et al., Proceedings of the National Academy of Sciences of the United States of America, 2010, vol. 107, p 18581). Intraperitoneal, subcutaneous, or intravenous administration of the test antibody (IgG) prior to the administration of LPS allows evaluation of effects of the test antibody on subsequent mortality of the mice. Inflammatory cytokines, such as IL-6 and TNF-α, are detected in blood at high concentrations within several hours after the administration of LPS. Anti-inflammatory effects of the test antibody can be evaluated by measuring concentrations of such inflammatory cytokines.

Example 18: Evaluation of In Vivo Effects on Cancer in Cancer-Bearing Mice

Murine or human cancer cell line cells are subcutaneously or intravenously transferred into mice, and are then administered with human IL-33. The number of cells to be transferred is appropriately determined depending on the cancer cell line, and the site of transfer is the same among animals. The mice are administered intraperitoneally, subcutaneously or intravenously with each test antibody (IgG), and are analyzed to confirm the number of cancer cells in the primary cancer site and in the metastatic lesion in other organ after the transfer of the cancer cell line cells on the basis of volume or cell count. The effects of each test antibody on cancer can be thereby evaluated.

Example 19: Evaluation of Colloidal Stability of Antibodies

Each test antibody (IgG) was analyzed to confirm colloidal stability by dynamic light scattering based on the presence of aggregates. Each alkaline-purified antibody was concentrated to a level of approximately 50 mg/mL with VIVASPIN or VIVASPIN TURBO (available from Sartorius AG; 10000 to 50000 MWCO). The centrifugation was performed at a temperature of 4° C., while the revolutions per minute and the duration were appropriately changed. The solution of each test antibody was sequentially diluted, and 200 to 250 μL of each sample was subjected to measurement of dynamic light scattering (Nanotrac UPA UT-151, available from NIKKISO CO., LTD.), to obtain data within a concentration range covering approximately 1 mg/mL to approximately 50 mg/mL. The particle size distribution of each antibody protein was calculated based on the data accumulated over 200 seconds, to evaluate the presence of aggregates. The particle size distribution of the test antibodies (A10-1C04, A23-1A05, A25-2C02, A25-3H04, and A26-1F02) showed a very slight peak shift from approximately 10 nm towards larger particle sizes along with the increase of antibody concentration, and did not have peak at particle size exceeding several tens of nanometers, i.e. it did not have a peak assumed not to be dependent on the antibody concentration but to be caused by irreversible aggregation. These results confirm that the test antibodies have excellent colloidal stability.

In order to quantitatively evaluate the colloidal stability, the interaction parameter (k_(D)) was calculated. The interaction parameter indicates concentration dependence of the diffusion coefficient (inversely proportional to the particle size), and is an important indicator used in formulation design of high-concentration protein formulations, such as antibodies. It is reported that an interaction parameter greater than −12.4 mL/g indicates high colloidal stability and low self-association due to repulsive interaction (Saito et al., Pharm. Res., 2013. Vol. 30 p. 1263). Each test antibody solution dissolved in PBS (at pH of 7.2) was concentrated by ultrafiltration to a concentration of several tens of mg/mL, and was subjected to serial doubling dilutions with the same solvent to prepare samples. Each sample was analyzed to confirm the particle size with a dynamic light scattering analyzer (Nanotrac UPA UT 151, available from NIKKISO CO., LTD.). Based on the measured particle size, the diffusion coefficient was calculated by the following Stokes-Einstein equation:

[Mathematical Formula 1]

where D is the diffusion coefficient (cm²/sec); K_(B) is the Boltzmann's constant (J/K); T is the thermodynamic temperature (K); π is the constant Pi; η is the viscosity P (poise) of the diluted solution; and d is the particle size (nm).

The concentration dependence of the diffusion coefficient was plotted, and the plot was fit to the following equation to determine the interaction parameter.

[Mathematical Formula 2]

where D is the diffusion coefficient calculated by the Stokes-Einstein equation; Do is the diffusion coefficient in the infinite dilution; and c is the measured concentration of each test antibody (g/mL). Based on the equation, the interaction parameter (k_(B)) representing the inclination of the fitting line was calculated. The results are as follows: A10-1C04 had an interaction parameter k_(D)=−8.1 mL/g (analytical range: 0.41-63.7 mg/mL); A23-1A05 had an interaction parameter k_(D)=−5.6 mL/g (analytical range: 0.40-61.8 mg/mL); A25-2C02 had an interaction parameter k_(D)=−6.2 mL/g (analytical range: 0.43-66.3 mg/mL); A25-3H04 had an interaction parameter k_(D)=−7.5 mL/g (analytical range of 0.34-56.5 mg/mL); A26-1F02 had an interaction parameter k_(D)=−6.7 mL/g (analytical range: 0.35-62.7 mg/mL). The results demonstrate that all the test antibodies had an interaction parameter exceeding −12.4 mL/g, indicating excellent colloidal stability.

Example 20: Evaluation of Thermodynamic Stability of Antibodies

Each test antibody (IgG) was analyzed to confirm thermodynamic stability at a temperature where the folding of immunoglobulin domain disappeared (Tm). Protein Thermal Shift Dye (Life Technologies) was added to each test antibody solution at a concentration of several tens of μg/mL in accordance with the instruction manual. The fluorescence intensity of the diluted solution was measured with Real-Time PCR 7500 Fast (Life Technologies) while the temperature was increased at a rate of about 1° C./min. The obtained data was analyzed with Protein Thermal Shift (Life Technologies) to determine the temperature Tm. If two or more temperatures Tm were observed, the lowest temperature was defined as Tm1, the second lowest temperature as Tm2, and so on. The results of evaluation of neutral-purified antibodies were as follows: A10-1C04 had Tm=73.9° C.; A23-1A05 had Tm1=69.3° C. and Tm2=77.6° C.; A25-2C02 had Tm1=69.3° C. and Tm2=80.3° C.; A25-3H04 had Tm1=70.0° C. and Tm2=76.4° C.; and A26-1F02 had Tm=74.5° C. The results of evaluation of alkaline-purified antibodies were as follows: A10-1C04 had Tm=73.7° C.; A23-1A05 had Tm1=69.5° C. and Tm2=77.5° C.; A25-2C02 had Tm1=69.5° C. and Tm2=80.4° C.; A25-3H04 had Tm1=70.1° C. and Tm2=76.4° C.; and A26-1F02 had Tm=74.4° C. The results indicate that all antibodies had a temperature Tm exceeding 65° C., demonstrating excellent thermodynamic stability.

Example 21: Evaluation of Preservation Stability of Antibodies

Each alkaline-purified antibody was dissolved in a citrate buffer (50 mM citric acid; 150 mM NaCl (pH: 6.3)) at a concentration of about 10 mg/mL, and was preserved at a temperature of 40° C. for four weeks, to evaluate the preservation stability of each test antibody (IgG). For evaluation of the monomer purity of each antibody after the preservation, monomer purity was measured by size exclusion chromatography analysis (SEC) and microchip capillary SDS electrophoresis (mCE-SDS), and antigen-binding activity was measured by surface plasmon resonance.

Two TSKgel G3000SWXL columns (available from Tosoh Bioscience LLC) were linked together and were mounted on an HPLC system (Beckman System Gold (126 solvent manager, 166 detector, and 508 auto sampler)) and gel filtration analysis was performed. The mobile phase solvent was 0.1 M phosphate buffer (at pH of 6.7) containing 0.1 M sodium sulfate. Each sample was separated at a flow rate of 0.5 mL/min, and was detected at absorbance of UV 215 nm. The sample for analysis was prepared by diluting about 10 mg/mL of the preserved antibody solution to 100-fold, and 50 μL of the sample for analysis was injected to the columns. Monomer purity determined by the size exclusion chromatography is shown in Table 13. The results indicate that all the test antibodies (A10-1C04, A23-1A05, A25-2C02, A25-3H04, and A26-1F02) retained a monomer purity exceeding 90% after preservation at a temperature of 40° C. for four weeks, demonstrating excellent preservation stability.

Capillary SDS electrophoresis was performed using Lab Chip GX II (available from PerkinElmer Inc.). Each sample was reduced with the reagent kit dedicated for the system, HT Protein Express Reagent (available from PerkinElmer Inc.), in accordance with the manufacturer's standard protocol, under denaturing conditions. As an analytical sample, 2 μL of preserved antibody solution with a concentration of about 10 mg/mL was added. The reagent used for the electrophoresis was taken from the kit and was added to a dedicated chip, HT Protein Express Lab Chip, version 2 (available from PerkinElmer Inc.), and the sample was measured in accordance with the built-in protocol for analysis of antibodies, HT Antibody 200. As shown in Table 13, under denaturing and reducing conditions, all the test antibodies (A10-1C04, A23-1A05, A25-2C02, A25-3H04, and A26-1F02) retained a monomer purity exceeding 90% after preservation at a temperature of 40° C. for four weeks, demonstrating excellent preservation stability.

In order to confirm the presence or absence of irreversible aggregation not dependent on the antibody concentration after the preservation, the particle size of each test antibody was measured. Each sample for analysis was prepared by diluting each preserved antibody solution to 10-fold with a citrate buffer (50 mM citric acid, 150 mM NaCl (pH: 6.3)) (final concentration: about 1 mg/mL), and was analyzed by dynamic light scattering technique (Nanotrac UPA UT-151, available from NIKKISO CO., LTD.) to measure the particle size of each test antibody. The accumulation time was 200 seconds. No aggregate was detected in the analysis of the test antibodies (A10-1C04, A23-1A05, A25-2C02, A25-3H04, A26-1F02, A00-0070, A00-0036) after preservation at a temperature of 40° C. for four weeks, demonstrating excellent preservation stability.

In order to confirm the presence of the antigen-binding ability after the preservation, the antigen-binding activity was measured with a surface plasmon resonance system, Biacore T200 (available from GE Healthcare). A human IL-33 protein (ILC0701, available from ATGen Co. Ltd) was immobilized onto a Sensor Chip CM5 (GE Healthcare) (the amount of immobilized protein was about 3000 to 6000 RU) with Amine Coupling Kit (GE Healthcare). Each preserved antibody solution was then diluted to 10-fold with a citric buffer (50 mM citric acid, 150 mM NaCl (pH: 6.3)), and the resulting solution was analyzed to measure the total protein concentration in the solution, using a microvolume spectrophotometer, Astragene II (Astranet Systems, Ltd.) (protein concentration: about 1 mg/mL). The antibody solution after the measurement of the total protein concentration was diluted to 1000-fold with HBS-EP buffer (10 mM HEPES, 150 mM NaCl, 3 mM EDTA, 0.05% (v/v) Surfactant P20 (at pH of 7.4)). The analyte was thereby prepared. The measurement temperature was 25° C. Each analyte was added for 36 seconds at two flow rates of 5 μL/min and 100 μL/min to obtain sensorgrams of the association phase. The sensorgrams were then analyzed by Calibration Free Concentration Analysis using a data analysis program (GE Healthcare, Biacore T200 Evaluation Software v1.0) to determine the concentration of the antibody having antigen-binding activity. As control, each test antibody after preservation at a temperature of 4° C. for four weeks was also analyzed to confirm the antigen-binding activity, to calculate the ratio of antigen-binding activity of each test antibody after the preservation at a temperature of 40° C. for four weeks. As shown in Table 13, all the test antibodies (A10-1C04, A23-1A05, A25-2C02, A25-3H04, and A26-1F02) retained antigen-binding activity exceeding 90% even after preservation at a temperature of 40° C. for four weeks, demonstrating excellent preservation stability.

TABLE 13 Preservation Stability at 40° C. for 4 W Antigen Binding SEC mCE-SDS Activity Antibody % monomer % monomer % Active IgG A23-1A05 95.8 97.7 101.8 A10-1C04 96.5 97.4 99.3 A26-1F02 95.9 98.2 101.1 A25-2C02 95.7 97.9 100.4 A25-3H04 95.8 98.0 101.8

Example 22: Evaluation of Stability of Antibodies by Forced Oxidation

Each test antibody (IgG) was analyzed to confirm influences of oxidation on its antigen-binding activity. To each alkaline-purified antibody with a final concentration of about 1 mg/mL, a hydrogen peroxide solution (final concentration: 1%) was added, and the resulting solution was oxidized at a temperature of 37° C. for 24 hours. To the resulting solution, 80 mM methionine solution was then added to stop oxidation. Each test antibody solution was then replaced with PBS with a desalting column, Zebaspin (available from Thermo Scientific). The oxidized test antibodies were each analyzed with a surface plasmon resonance system Biacore T200 (GE Healthcare) to confirm antigen-binding activity, as in Example 21. The ratio of antigen-binding activity of the oxidized antibody to that of untreated test antibody was calculated. The results are as follows: A10-1C04 retained 83% binding activity, A23-1A05 retained 95% binding activity, A25-2C02 retained 100.5% binding activity, A25-3H04 retained 98.7% binding activity, and A26-1F02 retained 89.5% binding activity. These results indicate that all the test antibodies (A10-1C04, A23-1A05, A25-2C02, A25-3H04, and A26-1F02) exhibited stability such that they retained antigen-binding activity exceeding 80% even after forced oxidation by treatment with 1% hydrogen peroxide solution.

Example 23: Evaluation of Aggregation Caused by Physical Stress (Stirring)

Each test antibody (IgG) was diluted with PBS to a concentration of 0.2 mg/mL, and the diluted solution was stirred in a batch cell placed on the Aggregates Sizer (available from Shimadzu Corporation) to apply physical stress. Each solution was stirred by vertical motion of stirring plate at a room temperature for 30 minutes (190 vibrations/min), and then was analyzed to confirm concentrations of aggregates having a particle size of 40 nm to 20 μm with the Aggregates Sizer. In the evaluation of each alkaline-purified antibody, the concentrations of aggregates produced by stirring were as follows: 17.2 μg/mL in A10-1C04; 16.4 μg/mL in A23-1A05; 13.3 μg/mL in A25-2C02; 23.4 μg/mL in A25-3H04; and 17.0 μg/mL in A26-1F02. The results indicate that all the antibodies exhibited 15% or less aggregation induced by physical stress, demonstrating that all the test antibodies were stable against physical stress.

Example 24: Evaluation of Plasma Concentration of the Antibodies in Mice

Each test antibody (IgG) was fluorescent-labeled, and was intravenously administered (3 mg/kg) to male C57BL6 mice (eight- to ten-weeks-old) (Charles River Laboratories International, Inc.). The concentration of the test antibody was measured by detecting the fluorescence in the plasma. As shown in FIG. 10, in the evaluation of each alkaline-purified antibody, all the test antibodies (A10-1C04, A23-1A05, A25-2C02, A25-3H04, and A26-1F02) had an elimination half-life of 100 hours or more, indicating good pharmacokinetic profile.

Example 25: Evaluation of Serum Concentration of the Antibodies in Monkeys

Each test antibody (IgG) (1 mg/kg) was intravenously administered to male cynomolgus monkeys (two- to three-years old) (Hamri Co., Ltd.), and then the serum concentration of the test antibody was measured with Human Therapeutic IgG1 EIA Kit (500910, available from Cayman Chemical). The alkaline-purified antibody A10-1C04 was administered to two cynomolgus monkeys (Nos. 201 and 202), and the alkaline-purified antibody A23-1A05 was administered to one cynomolgus monkey (No. 301). As shown in FIG. 11, the elimination half-life of A10-1C04 was 16.56 days (No. 201) and 11.40 days (No. 202), and the clearance was 3.598 mL/day/kg (No. 201) and 5.451 mL/day/kg (No. 202). A23-1A05 had an elimination half-life of 10.87 days, and a clearance of 10.07 mL/day/kg. Both test antibodies exhibited good pharmacokinetic profiles in cynomolgus monkeys.

Example 26: Evaluation of Immunogenicity of Antibodies

Each test antibody (IgG) was evaluated for immunogenicity potential by in vitro T-cell assay (LONZA Group Ltd.). Samples were collected from 50 donors to represent the target population, and 50 μg/mL of each alkaline-purified antibody was added to dendritic cells of human peripheral blood collected from the donors, so that the antibody was taken in the dendritic cells. CD4-positive T-cells of human peripheral blood collected from an identical donor were isolated. Subsequently, both cells, that is, the dendritic cells which had taken the test antibody and the CD4-positive T-cells, were co-cultured, to determine the reaction (proliferation) of the CD4-positive T-cells. As a negative control, a buffer (PBS) not containing any test antibody was used in the same reaction of CD4-positive T-cells, and the results were compared to evaluate the immunogenicity potential of each antibody. The results indicate that none of the test antibodies (A10-1C04, A25-2C02, A25-3H04, and A26-1F02) showed immunogenicity potential in the test condition

Example 27: Evaluation of Human Tissue Cross-Reactivity

Each test antibody (IgG) was evaluated for cross-reactivity to human tissues (frozen specimen of 35 tissues which satisfy the FDA and EMA guidelines, from one donor) by immunohistochemical staining (Covance Laboratories Ltd.). The 35 tissues include adrenal gland, bladder, blood cells, bone marrow, mammary gland, cerebellum, cerebral cortex, colon, endothelial cells (blood vessel), eyeball, oviduct, gastrointestinal tract (including smooth muscle), heart, kidney (glomerulus and renal tubule), liver, lung, lymph node, ovary, pancreas, parathyroid gland, parotid gland, peripheral nerve, pituitary gland, placenta, prostate gland, skin, spinal cord, spleen, striated muscle, testis, thymus, thyroid, tonsil, ureter, and uterus (cervical region and, endometrium). As a result, in the evaluation of alkaline-purified antibodies, all the test antibodies (A10-1C04, A23-1A05, A26-1F02, and A25-2C02) intensively stained vascular endothelial cells (positive control). IL-33 is known to be broadly expressed in the vascular endothelial cells. In various tissues such as epithelium, interstitial cells, neural tissues, muscular tissues, and hemocytes, cross-reactivity to the cytoplasm or nucleus was confirmed, but cross-reactivity to the cytoplasmic membrane was not observed in any tissue. According to the ICH S6(R1) guidelines and other articles (Toxicologic Pathology 2010, 38(7):1138-1166), cross-reactivity to the cytoplasm or nucleus, where an antibody is less likely to reach in vivo, has less toxicological significance. Therefore, none of the test antibodies (A10-1C04, A23-1A05, A26-1F02, and A25-2C02) exhibited toxicological concern.

Example 28: Narrowing of the Epitope Regions of A10-1C04 and A25-3H04

The anti-IL-33 monoclonal antibodies A10-1C04 and A25-3H04 bound to the epitope PEP14 as described in the Example 1. Experiments were performed with a phage display library of continuous amino acid sequences that are included in PEP14 consisting of 20 amino acids and are shorter than PEP14, and two different epitopes (LEDESYEIYV (SEQ ID NO:426 in the Sequence Listing) and EDESYEIYV (SEQ ID NO:427 in the Sequence Listing)) were found. The peptide LEDESYEIYV corresponds to the sequence spanning residues 138 to 147 of human IL-33 shown in SEQ ID NO:226 in the Sequence Listing, and the peptide EDESYEIYV corresponds to the sequence spanning residues 139 to 147 of human IL-33 shown in SEQ ID NO:226 in the Sequence Listing. These peptides were synthesized, and the affinity with the alkali-purified antibodies was calculated as Kd by the KinExA experiment as in Example 9 (Table 14).

TABLE 14 Kd Peptide A10-1C04 A25-3H04 DQSITFALEDESYEIYVEDL   9.0 nM  1.5 pM (PEP14) LEDESYEIYV  386.2 nM  11.0 nM EDESYEIYV 2070.0 nM 301.3 nM

INDUSTRIAL APPLICABILITY

The antibody with neutralizing effect of the present invention can be used as a pharmaceutical composition for diagnosis, treatment, prevention, or alleviation of diseases associated with IL-33. 

What is claimed is:
 1. A monoclonal antibody that is capable of binding to an epitope consisting of a continuous amino acid sequence included in positions 101 to 154 or 199 to 270 of SEQ ID NO:226 in the Sequence Listing.
 2. The antibody according to claim 1, wherein the epitope consisting of a continuous amino acid sequence included in positions 101 to 154 or 199 to 270 of SEQ ID NO:226 in the Sequence Listing is an epitope consists of a continuous amino acid sequence included in positions 111 to 130, 131 to 150, 231 to 250, or 251 to 270 of SEQ ID NO:226 in the Sequence Listing.
 3. The antibody according to claim 1, wherein the epitope consisting of a continuous amino acid sequence included in positions 101 to 154 or 199 to 270 of SEQ ID NO:226 in the Sequence Listing is an epitope consisting of an amino acid sequence including an amino acid selected from P118, I119, T120, Y122, L123, R124, S125, L126, S127, Y129, N130, D131, Q132, S133, T135, A137, L138, E139, S142, Y143, E144, I145, Y146, E148, D149, L150, D244, N245, H246, K266, L267, S268, and E269.
 4. The antibody according to claim 1, wherein the epitope consisting of a continuous amino acid sequence included in positions 101 to 154 or 199 to 270 of SEQ ID NO:226 in the Sequence Listing is an epitope consisting of a continuous amino acid of positions 111 to 130, 131 to 150, 231 to 250, or 251 to 270 of SEQ ID NO:226 in the Sequence Listing.
 5. The antibody according to claim 1, wherein the epitope consisting of a continuous amino acid sequence included in positions 101 to 154 or 199 to 270 of SEQ ID NO:226 in the Sequence Listing is an epitope consisting of a continuous amino acid sequence of positions 138 to 147 or 139 to 147 of SEQ ID NO:226 in the Sequence Listing.
 6. The antibody according to claim 1, wherein the monoclonal antibody that is capable of binding to the epitope consisting of a continuous amino acid sequence included in positions 101 to 154 or 199 to 270 of SEQ ID NO:226 in the Sequence Listing is an IL-33 antagonist.
 7. The antibody according to claim 1, wherein the monoclonal antibody that is capable of binding to the epitope consisting of a continuous amino acid sequence included in positions 101 to 154 or 199 to 270 of SEQ ID NO:226 in the Sequence Listing inhibits binding between IL-33 receptors and IL-33.
 8. A pharmaceutical composition for treatment, prevention, or alleviation of a disease associated with IL-33 comprising the antibody according to claim
 1. 9. A cytokine expression inhibitor comprising the antibody according to claim
 1. 10. The inhibitor according to claim 9, wherein the inhibitor inhibits expression of TNF-α, IFN-γ, IL-1β, IL-4, IL-5, IL-6, or IL-13.
 11. The inhibitor according to claim 9, wherein the inhibitor inhibits expression of IFN-γ, IL-5, IL-6, or IL-13.
 12. An epitope selected from the group consisting of: 1) the epitope according to claim 1; 2) an epitope consisting of an amino acid sequence including one or several amino acid substitutions, deletions, or additions as compared to the continuous amino acid sequence of the epitope; and 3) an epitope consisting of an amino acid sequence with at least 90% sequence identity to the continuous amino acid sequence of the epitope.
 13. An antibody generated or screened using the epitope according to claim
 12. 14. The antibody according to claim 1, wherein the monoclonal antibody that is capable of binding to the epitope consisting of a continuous amino acid sequence included in positions 101 to 154 or 199 to 270 of SEQ ID NO:226 in the Sequence Listing is a chimeric, a humanized, or a human antibody.
 15. The antibody according to claim 14, wherein the amino acid sequences of the framework regions is amino acid sequences of framework regions from a human germline or a combination of amino acid sequences thereof.
 16. The antibody according to claim 15, wherein the amino acid sequence of the light-chain framework region 1 is residues 1 to 22 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 2 is residues 36 to 50 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 3 is residues 58 to 89 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 4 is residues 3 to 12 of SEQ ID NO:401 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 1 is residues 1 to 30 of SEQ ID NO:367 or residues 1 to 30 of SEQ ID NO:368 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 2 is residues 36 to 49 of SEQ ID NO:367 or residues 36 to 49 of SEQ ID NO:368 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 3 is residues 67 to 98 of SEQ ID NO:367 or residues 67 to 98 of SEQ ID NO:368 in the Sequence Listing; and the amino acid sequence of the heavy-chain framework region 4 is residues 5 to 15 of SEQ ID NO:407 in the Sequence Listing.
 17. The antibody according to claim 15, wherein the amino acid sequence of the light-chain framework region 1 is residues 1 to 22 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 2 is residues 36 to 50 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 3 is residues 58 to 89 of SEQ ID NO:317 in the Sequence Listing; the amino acid sequence of the light-chain framework region 4 is residues 3 to 12 of SEQ ID NO:401 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 1 is residues 1 to 30 of SEQ ID NO:367 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 2 is residues 36 to 49 of SEQ ID NO:367 in the Sequence Listing; the amino acid sequence of the heavy-chain framework region 3 is residues 67 to 98 of SEQ ID NO:368 in the Sequence Listing; and the amino acid sequence of the heavy-chain framework region 4 is residues 5 to 15 of SEQ ID NO:407 in the Sequence Listing.
 18. The pharmaceutical composition according to claim 8 for treatment, prevention, or alleviation of a disease associated with IL-33.
 19. The pharmaceutical composition according to claim 8, wherein the disease associated with IL-33 is selected from the group consisting of asthma, atopic dermatitis, pollinosis, anaphylactic shock, sinusitis (including eosinophilic sinusitis), Crohn's disease, ulcerative colitis, arthritis, systemic lupus erythematosus, pemphigus, pemphigoid, scleroderma, ankylosing spondylitis, hepatic fibrosis (including primary biliary cirrhosis), pulmonary fibrosis, chronic obstructive pulmonary disease (COPD), acute kidney injury, vasculitis, Sjogren's syndrome and cancer. 